[github] Add Unstable Test Reporter for CI to track flaky tests

Author: wuchong

.github/workflows/unstable-test-reporter.yaml

@@ -0,0 +1,51 @@
+################################################################################
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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.
+################################################################################
+name: Unstable Test Reporter
+on:
+  schedule:
+    # Run at UTC 04:00 daily (after Nightly at UTC 20:00 + buffer for completion)
+    - cron: "0 4 * * *"
+  workflow_dispatch:
+    inputs:
+      lookback_hours:
+        description: "Hours to look back for failed runs"
+        required: false
+        default: "28"
+
+permissions:
+  issues: write
+  actions: read
+
+jobs:
+  report:
+    name: "Report Unstable Tests"
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.11"
+      - name: Install dependencies
+        run: pip install requests
+      - name: Run unstable test reporter
+        run: python tools/ci/unstable_test_reporter.py
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          LOOKBACK_HOURS: ${{ inputs.lookback_hours || '28' }}