The `PluginManager.hasPlugin` method was not detecting the GE plugin when it
was applied during settingsEvaluated.
Switching to `PluginManager.withPlugin` fixes this.
Fixes#626
When configuration-cache is enabled, the invocationId may not be unique, which can result in
mulitple builds writing to the same file. Rather than failing the post-action, we simply
ignore any subsequent build results with the same ID.
Fixes#441
The init-scripts added to Gradle User Home were assuming the presence of certain
GitHub Actions environment variables. With this fix, these init scripts behave
better without these env vars.
Fixes#350