Consider setting @SupportedSourceVersion to SourceVersion.RELEASE_17

[mkjensen]

Since you are already preparing for Spring Boot 3 and Java 17 (#1433), maybe you can also consider changing https://github.com/zalando/zally/blob/main/server/zally-core/src/main/kotlin/org/zalando/zally/core/RuleProcessor.kt from @SupportedSourceVersion(SourceVersion.RELEASE_11) to @SupportedSourceVersion(SourceVersion.RELEASE_17).

Then we can avoid the following Maven warning in a Spring Boot 3 project:

[WARNING] Supported source version 'RELEASE_11' from annotation processor 'org.zalando.zally.core.RuleProcessor' less than -source '17'

Thanks.

[ePaul]

Could you open a pull request for this? Then it can fit into the next release.

Thanks!