.github: fix permissions issue on pr review request on forks

[MSevey]

Overview

The housingkeeping workflow was failing due to forks not having write access during workflow runs. This is for security reasons. However there are many non-security critical tasks that require write access, such as requesting reviewers or making comments on a PR. For these, the pull_request_target trigger can be used, as it allows write access to forks for the select workflows.

I tested this on a personal github org and it worked for both native branches and forks.

NOTE: the reason the workflow is not running on this PR is because of the chicken and egg issue of updating workflows, in that the update needs to be on main in order for it to run.

Closes celestiaorg/.github#19

Checklist

• New and updated code has appropriate documentation
• New and updated code has new and/or updated testing
• Required CI checks are passing
• Visual proof for any user facing features like CLI or documentation updates
• Linked issues closed with keywords

[rootulp]

🙏