Update build release artifacts workflow to include release notes (#4568)

Author: rlazo

.github/workflows/build-release-artifacts.yml

@@ -17,9 +17,15 @@ jobs:
       - name: Perform gradle build
         run: |
           ./gradlew firebasePublish -PpublishConfigFilePath=release.cfg -PpublishMode=RELEASE -PincludeFireEscapeArtifacts=true
+
+      - name: Generate release notes
+        run: |
+          python3 docs/make_release_notes.py
+          cd build/changelog && zip -r ../release_notes.zip android
+
       - name: Upload generated artifacts
         uses: actions/upload-artifact@v2
         with:
           name: release_artifacts
           path: build/*.zip
-          retention-days: 5
+          retention-days: 15