chore: add stale workflow (#713)

.github/workflows/stale.yaml

@@ -0,0 +1,34 @@
+# Copyright 2022-2024 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# NOTE: This file is taken from:
+# https://github.com/GoogleCloudPlatform/cloud-foundation-toolkit/blob/master/infra/terraform/test-org/github
+
+name: "Close stale issues"
+on:
+  schedule:
+  - cron: "0 23 * * *"
+
+jobs:
+  stale:
+    if: github.repository_owner == 'GoogleCloudPlatform' || github.repository_owner == 'terraform-google-modules'
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/stale@v9
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
+        stale-issue-message: 'This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days'
+        stale-pr-message: 'This PR is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days'
+        exempt-issue-labels: 'triaged'
+        exempt-pr-labels: 'dependencies,autorelease: pending'