ci : move close-issue.yml to .github/workflows [no ci] (#4002)

This commit moves the close-issue.yml file to the .github/workflows/
directory.

The motivation for this is that it is currently in the root of the repo
and is not currently active. Moving it to the workflows directory will
make it active and allow it to run.

.github/workflows/close-issue.yml

@@ -0,0 +1,28 @@
+name: Close inactive issues
+on:
+  schedule:
+    - cron: "42 0 * * *"
+
+# Fine-grant permission
+# https://docs.github.com/en/actions/security-for-github-actions/security-guides/automatic-token-authentication#modifying-the-permissions-for-the-github_token
+permissions:
+  issues: write
+
+jobs:
+  close-issues:
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+      pull-requests: write
+    steps:
+      - uses: actions/stale@v10
+        with:
+          exempt-issue-labels: "refactor,help wanted,good first issue,research,bug,roadmap"
+          days-before-issue-stale: 30
+          days-before-issue-close: 14
+          stale-issue-label: "stale"
+          close-issue-message: "This issue was closed because it has been inactive for 14 days since being marked as stale."
+          days-before-pr-stale: -1
+          days-before-pr-close: -1
+          operations-per-run: 10000
+          repo-token: ${{ secrets.GITHUB_TOKEN }}