Reactivate Checkstyle

[wadoon]

Someone deactivated Sonarqube. We seem to have a deeper inner confusion with our common understanding of clean code.

First, this PR reactivates the Checkstyle on changed files still within Gradle.

1. Checkstyle is executed on all changed files in comparison to origin/main. This solution does not respect lines.
2. Reporting works overall possible reliable ways:
   1. Markdown Job summary is added
      
   2. A Sarif file is uploaded to the repository:
      
   3. Artifact can be downloaded:
      
   4. It does not add a comment to the PR as this is not reliable due to reduced permissions on workflow executions for foreign repositories.

Second, it also brings some updates w.r.t. deprecation warnings and hints in/for Gradle.

1. task.register is prior to just task <name> due to laziness in initialization
2. Variable $buildDir is deprecated and we should use layout.buildDirectory
3. Jacoco is now integrated in the regular Gradle files (no conditional loading anymore), and the enabled switch is used for activation/deactiviation.
4. At the end of the Github tests runs, a Python scripts runs through the JUnit test summaries and prints out Github annotations.
5. Increment Gradle version

[github-advanced-security]

This pull request sets up GitHub code scanning for this repository. Once the scans have completed and the checks have passed, the analysis results for this pull request branch will appear on this overview. Once you merge this pull request, the 'Security' tab will show more code scanning analysis results (for example, for the default branch). Depending on your configuration and choice of analysis tool, future pull requests will be annotated with code scanning analysis results. For more information about GitHub code scanning, check out the documentation.

[wadoon]

Missing check, if no Java files were altered.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 38.39%. Comparing base (181fb2a) to head (1947eb5).
Report is 36 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #3539   +/-   ##
=========================================
  Coverage     38.39%   38.39%           
  Complexity    17238    17238           
=========================================
  Files          2099     2099           
  Lines        127342   127342           
  Branches      21446    21446           
=========================================
  Hits          48890    48890           
  Misses        72440    72440           
  Partials       6012     6012           

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[mattulbrich]

Someone deactivated Sonarqube. We seem to have a deeper inner confusion with our common understanding of clean code.

If there is confusion, should that not be cleared first? What is the confusion about?

[wadoon]

If there is confusion, should that not be cleared first? What is the confusion about?

This was just an euphemism for we agreed on Sonarcube, set up the rules, and someone deactivates it. This leads to questions.

[mattulbrich]

The newly introduced check still fails.

Regarding tools like SonarCube:
CodeQuality measuring gates help improve the code. However, they must work properly. If they fail consistently and are not repaired, they should be turned off.