github_actions: Add a GitHub action for notifying if API docs changed.

.github/workflows/api-docs-update-check.yml

@@ -1,4 +1,4 @@
-name: Check feature level updated
+name: API Documentation Update Check
 
 on:
   push:
@@ -7,6 +7,9 @@ on:
       - "api_docs/**"
   workflow_dispatch:
 
+permissions:
+  contents: read
+
 jobs:
   check-feature-level-updated:
     runs-on: ubuntu-latest
@@ -22,9 +25,6 @@ jobs:
         with:
           python-version: "3.x"
 
-      - name: Add required permissions
-        run: chmod +x ./tools/check-feature-level-updated
-
       - name: Run tools/check-feature-level-updated
         id: run_check
         run: ./tools/check-feature-level-updated >> $GITHUB_OUTPUT
@@ -44,3 +44,37 @@ jobs:
       - name: Fail job if feature level not updated in API docs
         if: ${{ steps.run_check.outputs.fail == 'true' }}
         run: exit 1
+
+  notify-if-api-docs-changed:
+    runs-on: ubuntu-latest
+    needs: check-feature-level-updated
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.x"
+
+      - name: Add required permissions
+        run: chmod +x ./tools/notify-if-api-docs-changed
+
+      - name: Run tools/notify-if-api-docs-changed
+        id: run_check
+        run: ./tools/notify-if-api-docs-changed >> $GITHUB_OUTPUT
+
+      - name: Report status to CZO
+        if: ${{github.repository == 'zulip/zulip'}}
+        uses: zulip/github-actions-zulip/send-message@v1
+        with:
+          api-key: ${{ secrets.ZULIP_BOT_KEY }}
+          email: "github-actions-bot@chat.zulip.org"
+          organization-url: "https://chat.zulip.org"
+          to: "api documentation"
+          topic: ${{ steps.run_check.outputs.topic }}
+          type: "stream"
+          content: ${{ steps.run_check.outputs.content }}