Add summary step to packaging step

Same step as the integration test workflow.

Author: anonymous-akorn

.github/workflows/cpp-packaging.yml

@@ -676,3 +676,7 @@ jobs:
       if: matrix.target_platform != 'Desktop' && !cancelled()
       run: |
         python scripts/gha/test_lab.py --android_model ${{ env.android_device }} --android_api ${{ env.android_api }} --ios_model ${{ env.ios_device }} --ios_version ${{ env.ios_version }} --testapp_dir testapps --code_platform cpp --key_file scripts/gha-encrypted/gcs_key_file.json
+    - name: Summarize build and test results
+      if: ${{ !cancelled() }}
+      shell: bash
+      run: cat testapps/summary.log