Yes, this is the typical simple PHP 8 fix that needs to go into core. If you can, please open the Issue, and you can even create a PR with the fix.
Pr that touch only one file are simple to create from Github. Just go to the file on the correct (hotfix) branch and click the pencil icon to edit the file.
Github will offer to create the fork for you. Then you will have to save twice: once for the commit, a second time for the PR with the commit. Github guides you with big green buttons so you know what to press.