Remove on-reopen workflow (#224334)

.github/workflows/on-reopen.yml

@@ -1,22 +0,0 @@
-name: On Reopen
-on:
-  issues:
-    types: [reopened]
-
-jobs:
-  main:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout Actions
-        uses: actions/checkout@v4
-        with:
-          repository: "microsoft/vscode-github-triage-actions"
-          ref: stable
-          path: ./actions
-      - name: Install Actions
-        run: npm install --production --prefix ./actions
-
-      - name: Check for Validity
-        uses: ./actions/validity-checker
-        with:
-          token: ${{secrets.VSCODE_ISSUE_TRIAGE_BOT_PAT}}