chore(ci): Disable codeowners-coverage workflow (#112390)

Disabling the `codeowners-coverage` for now as it is an optional check
and people are getting flagged to fix things unrelated to their PR. We
should only be flagging people that touch unowned things as the
implication is they’re in a position to understand those things. We will
re-enable after improving this check.

Disables the `codeowners-coverage` GitHub Actions workflow by commenting
out the `pull_request` trigger and switching to `workflow_dispatch`
only. This prevents the workflow from running automatically on PRs while
still allowing manual triggering if needed.

---------

Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: bc-sentry

.github/workflows/codeowners-coverage.yml

@@ -6,7 +6,8 @@ on:
   # push:
   #   branches:
   #     - master
-  pull_request:
+  # pull_request:
+  workflow_dispatch:
 
 # Cancel in progress workflows on pull_requests.
 # https://docs.github.com/en/actions/using-jobs/using-concurrency#example-using-a-fallback-value