Run Maestro flow only then Run-Maestro label is present in a PR (#1852)

* Run Maestro only when the `Run-Maestro` label is present in a PR.

.github/workflows/maestro.yml

@@ -1,11 +1,10 @@
 name: Maestro
 
-# Run this flow only on pull request, and only when the pull request has been approved, to limit our usage of maestro cloud.
+# Run this flow only on pull request, and only when the pull request has the Run-Maestro label, to limit our usage of maestro cloud.
-# https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#running-a-workflow-when-a-pull-request-is-approved
 on:
   workflow_dispatch:
-  pull_request_review:
+  pull_request:
-    types: [submitted]
+    types: [labeled]
 
 # Enrich gradle.properties for CI/CD
 env:
@@ -16,7 +15,7 @@ jobs:
   maestro-cloud:
     name: Maestro test suite
     runs-on: ubuntu-latest
-    if: github.event.review.state == 'approved' || github.event_name == 'workflow_dispatch'
+    if: github.event_name == 'workflow_dispatch' || github.event.label.name == 'Run-Maestro'
     strategy:
       fail-fast: false
     # Allow one per PR.
@@ -24,6 +23,11 @@ jobs:
       group: ${{ format('maestro-{0}', github.ref) }}
       cancel-in-progress: true
     steps:
+      - name: Remove Run-Maestro label
+        if: ${{ github.event.label.name == 'Run-Maestro' }}
+        uses: actions-ecosystem/action-remove-labels@v1
+        with:
+          labels: Run-Maestro
       - uses: actions/checkout@v4
         with:
           # Ensure we are building the branch and not the branch after being merged on develop