Github actions are not executed for pull requests

[kh31d4r]

https://github.com/mosbth/irc2phpbb/pull/58/checks

[foikila]

Ops, forgot that... Should be a simple fix by adding a new trigger like this: https://docs.github.com/en/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows#pull_request