Support configuration cache

[JordanLongstaff]

I tried adding this plugin to my repo and running the grabverRelease task, and got this output:

Execution failed for task ':app:grabverRelease'.
> Invocation of 'Task.project' by task ':app:grabverRelease' at execution time is unsupported with the configuration cache.

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Ask Gemini

Furthermore, Gradle reported cache problems:

Configuration cache problems found in this build.

3 problems were found storing the configuration cache.
- Plugin 'eu.davidea.grabver': registration of listener on 'Gradle.buildFinished' is unsupported
  See https://docs.gradle.org/9.1.0/userguide/configuration_cache_requirements.html#config_cache:requirements:build_listeners
- Plugin 'eu.davidea.grabver': registration of listener on 'TaskExecutionGraph.afterTask' is unsupported
  See https://docs.gradle.org/9.1.0/userguide/configuration_cache_requirements.html#config_cache:requirements:build_listeners
- Task `:app:grabverRelease` of type `org.gradle.api.DefaultTask`: invocation of 'Task.project' at execution time is unsupported with the configuration cache.
  See https://docs.gradle.org/9.1.0/userguide/configuration_cache_requirements.html#config_cache:requirements:use_project_during_execution

Configuration cache has been a stable feature of Gradle since 8.1. Please add support for it.