Upgrade build toolchain

[programming-wolf]

• Remove Java workaround script
• Include submodule for gradle-tools
• Reduce build.gradle code as it was all moved to the gradle-tools submodule

Note: This will break the build chain. I have adjusted the build files in a feature branch. We then have to update all the repositories in one step.

close #156

[github-actions]

Build Successful! You can find a link to the downloadable artifacts below.

Name	Link
Commit	2bdd454
Logs	https://github.com/isaqb-org/advanced-template/actions/runs/10850109228
Download	https://github.com/isaqb-org/advanced-template/suites/28357577617/artifacts/1929944276

[alexanderschramm1992]

In den Workflow Files werden die Versionen des Test Branches gezogen. Sicher, dass das nicht der Main Branch sein soll?

[alexanderschramm1992]

Migrationspfad (Test Branch -> Main Branch) besprochen, daher approved