[gradle] generate initial files for convention plugin usage

[atomfrede]

This PR adds the needed "infrastructure" part to use gradle convention plugins.

updates #19615

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[atomfrede]

Strange behaviour with checkstyle/nohttp and dependency resolution, which I didn't had when trying it out. It worked yesterday, so maybe some issue with upstream things. Will have a look later.

[atomfrede]

The dependency resolution issue is tracked at checkstyle here: checkstyle/checkstyle#14123 for now i have applied the workaround described here

[mshima]

From your sample, gradle plugins uses the format id 'plugin'.
At current implementation you are adding a dependency instead of a plugin.
Is this the desired behavior?

[atomfrede]

@mshima This is just the "infrastructure" inside buildSrc folder. So adding a dependency is correct. These are needed dependencies for the convention plugins. One need to add third party plugins to the dependencies block inside buildSrc/build.gradle to use them within the convention plugins. See https://github.com/atomfrede/jhipster-gradle-improvements/blob/main/buildSrc/build.gradle

Applying and creating convention plugins will be separate PRs.