icu: modernize more for conan v2

[SpaceIm]

• use new stdcpp_library() instead of legacy one (since conan 1.54.0)
• write custom _sha256sum() function to avoid relying on legacy conans.tools.sha256sum() conan function
• remove workaround for [bug] When cross building AutotoolsToolchain does not pass --build option if there is any configure argument with "build" in its name conan#12642 (fixed in conan 1.57.0)
• remove workaround for [bug] conan.tools.gnu.Autotools.install() doesn't work if build machine is Windows conan#12153 (fixed in conan 1.54.0)

There is still a legacy function: get_gnu_triplet(). See conan-io/conan#13028

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• I've read the contributing guidelines.
• I've used a recent Conan client version close to the currently deployed.
• I've tried at least one configuration locally with the conan-center hook activated.

[ghost]

I detected other pull requests that are modifying icu/all recipe:

• icu: validate dat package file exists #14980

This message is automatically generated by https://github.com/ericLemanissier/conan-center-conflicting-prs so don't hesitate to report issues/improvements there.

[conan-center-bot]

Conan v1 pipeline ✔️

All green in build 4 (8a8697a8b23322c1ca56bd2d4468775246cc51f6):

• icu/72.1@:
  All packages built successfully! (All logs)

• icu/69.1@:
  All packages built successfully! (All logs)

• icu/70.1@:
  All packages built successfully! (All logs)

• icu/66.1@:
  All packages built successfully! (All logs)

• icu/65.1@:
  All packages built successfully! (All logs)

• icu/68.2@:
  All packages built successfully! (All logs)

• icu/71.1@:
  All packages built successfully! (All logs)

• icu/67.1@:
  All packages built successfully! (All logs)

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Conan v2 pipeline (informative, not required for merge) ❌

Note: Conan v2 builds are informative and they are not required for the PR to be merged.

The v2 pipeline failed. Please, review the errors and note this will be required for pull requests to be merged in the near future.

See details:

Failure in build 6 (8a8697a8b23322c1ca56bd2d4468775246cc51f6):

• icu/72.1@:
  Error running command conan export --name icu --version 72.1 recipes/icu/all/conanfile.py:

  ERROR: Error loading conanfile at '/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py': Unable to load conanfile in /home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py", line 10, in <module>
      from conans.tools import get_gnu_triplet
  ModuleNotFoundError: No module named 'conans.tools'
  

• icu/70.1@:
  Error running command conan export --name icu --version 70.1 recipes/icu/all/conanfile.py:

  ERROR: Error loading conanfile at '/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py': Unable to load conanfile in /home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py", line 10, in <module>
      from conans.tools import get_gnu_triplet
  ModuleNotFoundError: No module named 'conans.tools'
  

• icu/71.1@:
  Error running command conan export --name icu --version 71.1 recipes/icu/all/conanfile.py:

  ERROR: Error loading conanfile at '/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py': Unable to load conanfile in /home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py", line 10, in <module>
      from conans.tools import get_gnu_triplet
  ModuleNotFoundError: No module named 'conans.tools'
  

• icu/69.1@:
  Error running command conan export --name icu --version 69.1 recipes/icu/all/conanfile.py:

  ERROR: Error loading conanfile at '/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py': Unable to load conanfile in /home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py", line 10, in <module>
      from conans.tools import get_gnu_triplet
  ModuleNotFoundError: No module named 'conans.tools'
  

• icu/68.2@:
  Error running command conan export --name icu --version 68.2 recipes/icu/all/conanfile.py:

  ERROR: Error loading conanfile at '/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py': Unable to load conanfile in /home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py", line 10, in <module>
      from conans.tools import get_gnu_triplet
  ModuleNotFoundError: No module named 'conans.tools'
  

• icu/67.1@:
  Error running command conan export --name icu --version 67.1 recipes/icu/all/conanfile.py:

  ERROR: Error loading conanfile at '/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py': Unable to load conanfile in /home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py", line 10, in <module>
      from conans.tools import get_gnu_triplet
  ModuleNotFoundError: No module named 'conans.tools'
  

• icu/66.1@:
  Error running command conan export --name icu --version 66.1 recipes/icu/all/conanfile.py:

  ERROR: Error loading conanfile at '/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py': Unable to load conanfile in /home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py", line 10, in <module>
      from conans.tools import get_gnu_triplet
  ModuleNotFoundError: No module named 'conans.tools'
  

• icu/65.1@:
  Error running command conan export --name icu --version 65.1 recipes/icu/all/conanfile.py:

  ERROR: Error loading conanfile at '/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py': Unable to load conanfile in /home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod-v2_cci_PR-15778/recipes/icu/all/conanfile.py", line 10, in <module>
      from conans.tools import get_gnu_triplet
  ModuleNotFoundError: No module named 'conans.tools'
  

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