SQSCANGHA-76 Support self-hosted runners not clearing truststore after run

[antonioaversa]

Kept in draft to avoid accidental merging into #165.

Originated from this discuss post.

Similar scenario as #164 (self-hosted Github runners), but for SSL certificates:

v4.1.0 of the sonarqube-scan-action GitHub Action fails in the following situation:

• The GitHub Action workflow is using a self-hosted runner.
• Additionally, the self-hosted runner is set up in such a way that a clean instance is not provided for each job execution. (See About self-hosted runners - GitHub Docs for more information about self-hosted runners.)
• The SONAR_ROOT_CERT environment variable is set in the sonarqube-scan-action step.

The warning appears like here

Update: change of behavior

Now, if the truststore.p12 exists already, we don't remove anymore the ~/sonar/ssl directory.
Instead, we check whether such truststore.p12 contains a sonar alias.
If it does, and only if it does, we remove the alias from the truststore, and then we proceed as usual.
If people really want to start with a clean truststore.p12, they can tune their agent.

Here is a successful run: https://github.com/SonarSource/sonarqube-scan-action/actions/runs/12355702818/job/34479954427?pr=165

[henryju]

Very nice, congrats for the test!