Update dependency pytest-cov to v6

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
pytest-cov (changelog)	^5.0.0 -> ^6.0.0

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Release Notes

pytest-dev/pytest-cov (pytest-cov)

v6.0.0

Compare Source

• Updated various documentation inaccuracies, especially on subprocess handling.
• Changed fail under checks to use the precision set in the coverage configuration.
  Now it will perform the check just like coverage report would.
• Added a --cov-precision cli option that can override the value set in your coverage configuration.
• Dropped support for now EOL Python 3.8.

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Configuration

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🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• If you want to rebase/retry this PR, check this box

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[renovate]

⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
• you click the rebase/retry checkbox if found above, or
• you rename this PR's title to start with "rebase!" to trigger it manually

The artifact failure details are included below:

File name: poetry.lock

Updating dependencies
Resolving dependencies...


The current project's Python requirement (>=3.8.1,<4.0.0) is not compatible with some of the required packages Python requirement:
  - pytest-cov requires Python >=3.9, so it will not be satisfied for Python >=3.8.1,<3.9

Because no versions of pytest-cov match >6.0.0,<7.0.0
 and pytest-cov (6.0.0) requires Python >=3.9, pytest-cov is forbidden.
So, because cf2tf depends on pytest-cov (^6.0.0), version solving failed.

  • Check your dependencies Python requirement: The Python requirement can be specified via the `python` or `markers` properties
    
    For pytest-cov, a possible solution would be to set the `python` property to ">=3.9,<4.0.0"

    https://python-poetry.org/docs/dependency-specification/#python-restricted-dependencies,
    https://python-poetry.org/docs/dependency-specification/#using-environment-markers