[Task]: Review remaining jira references in the codebase

### What needs to happen?

Context: https://github.com/apache/beam/pull/21835#discussion_r897400543

There are many references to jiras left in the codebase after the translation done for #21812. By definition these are all closed jiras, because all open jiras were migrated to GitHub Actions. So for each jira reference, either:
- the task is not actually complete, or
- the comment is obsolete

We should review all of the remaining jira references to determine which it is and address (either by re-opening the ticket, or removing the comment).

### Issue Priority

Priority: 2

### Issue Component

Component: project-management