Motivation

Currently, some GitHub workflows which are automatically triggered when a PR is created are failing due to the missing access to certain secrets
This PR should fix these issues such that workflow executions triggered by PRs coming from community forks can get fully green (after they have been approved by a contributor).
/cc @joe4dev

Changes

• Disables the Pro integration tests for community forks.
• Changes the workflow trigger for the label checks from pull_request to pull_request_target.
  • This is similar to the pr-cla action.
  • This trigger is executed on the default branch of the target repo, rather than in the branch, which prevents secret leaking.
  • This is why these workflows can access secrets other than the default github token.
  • More info on pull_request_target can be found here: https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#pull_request_target

Testing

• These changes are somewhat hard to test, since they need to be merged to the default branch before they can be properly tested if the execution works for forks now.
• Once this PR is merged, we can evaluate if the pipelines are now working for community raised fork-PRs.