chore: fix pr-labeler permissions (aws#17398)

Apparently, in order to add labels to a PR, the token must have write permissions to issues as well, otherwise it will silently fail.

See cli/cli#4631

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.github/workflows/pr-labeler.yml

@@ -11,6 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     permissions:
       pull-requests: write
+      issues: write
     steps:
     - run: gh pr edit ${{ github.event.pull_request.number }} --add-label "pr/auto-approve" -R ${{ github.repository }}
       env: