SQSCANGHA-51 Make Scanner CLI binaries URL customizable

[antonioaversa]

Why

CI pipelines in environments that impose strict control to the access to the www fail the wget instruction to download Sonar Scanner CLI from the sonarsource binaries site.

For those scenarios, we need to add additional parameters that users can use to point to a custom repository of binaries.

What

This PR introduces a new optional scannerBinariesUrl action parameter, that allows to set the URI to the CLI. The URI is up to the sonarscanner directory included (https://binaries.sonarsource.com/Distribution/sonar-scanner-cli), and doesn't include the name of the file (e.g. sonar-scanner-cli-6.2.1.4610-linux-x64.zip) since the name of the file depends on operating system (RUNNER_OS) and architecture (RUNNER_ARCH).

    - name: Dart Scan
      uses: sonarsource/sonarqube-scan-action@antonio/binaries-url-config
      env:
        SONAR_HOST_URL: http://localhost:9000
      with:
        scannerBinariesUrl: https://my.custom.binaries.url.com/Distribution/sonar-scanner-cli/

The new scannerBinariesUrl action parameter includes Distribution/sonarscanner so that's easy for a user who need to change it to a custom repo, to point to any directory, without the need to recreate the Distribution/sonarscanner structure.

This means that, the day we will need to download another resource from binaries.sonarsource.com, we will need to add another parameter. Build wrapper, however, won't pose such a problem since it is downloaded from SonarQube.

Builds

Successful build with default value: https://github.com/antonioaversa/dart-tools-test1/actions/runs/11897272492/job/33151305671#step:4:40
Successful build with explicit default value (terminal slash): https://github.com/antonioaversa/dart-tools-test1/actions/runs/11896758678/job/33149767749#step:4:40
Successful build with a different URI, containing the required binary: https://github.com/antonioaversa/dart-tools-test1/actions/runs/11896649263/job/33149029847#step:4:40
Failing build with a different URI, non-containing the required binary: https://github.com/antonioaversa/dart-tools-test1/actions/runs/11896323568/job/33148487407#step:4:43

[antonioaversa]

This test was missing. While it is not strictly in scope for the change, but helped as intermediate testing step to come up with a valid test for scannerBinariesUrl.

[antonioaversa]

I needed to add this NO_CACHE parameter to ignore previously cached scanners.
Clearing the cache via gh cache delete is possible but requires repo-scope permissions (see here).