Remove stale workflow (#735)

.github/workflows/stale.yml

@@ -1,19 +0,0 @@
-name: 'Close stale issues and PRs'
-on:
-  schedule:
-    - cron: '40 2/3 * * *'
-
-jobs:
-  stale:
-    runs-on: ubuntu-latest
-    env:
-      YARN_ENABLE_SCRIPTS: false
-    steps:
-      - uses: actions/stale@v7
-        with:
-          repo-token: ${{ secrets.GH_PAT_BOT }}
-          stale-issue-message: 'This issue has been open for 365 days with no activity and is not labelled as an enhancement. It will be closed in 7 days.'
-          stale-issue-label: 'stale'
-          exempt-issue-labels: '-size-l,-size-m,-size-s,-size-xl,-size-xs,[bug]'
-          days-before-stale: 365
-          days-before-close: 7