Upload files to GCS only for pushes to relese and release candidate b…

…ranches

.github/workflows/build_wheels.yml

@@ -68,6 +68,7 @@ jobs:
     name: Prepare GCS
     needs: build_source
     runs-on: ubuntu-latest
+    if: github.event_name != 'pull_request'
     steps:
       - name: Authenticate on GCP
         uses: GoogleCloudPlatform/github-actions/setup-gcloud@master
@@ -97,7 +98,7 @@ jobs:
 
   build_wheels:
     name: Build wheels on ${{ matrix.os }}
-    needs: prepare_gcs
+    needs: build_source
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
@@ -131,6 +132,7 @@ jobs:
     name: Upload wheels to GCS bucket
     needs: build_wheels
     runs-on: ubuntu-latest
+    if: github.event_name != 'pull_request'
     strategy:
       matrix:
         os : [ubuntu-latest, macos-latest]
@@ -152,6 +154,7 @@ jobs:
     name: List files on Google Cloud Storage Bucket
     needs: upload_wheels_to_gcs
     runs-on: ubuntu-latest
+    if: github.event_name != 'pull_request'
     steps:
     - name: Authenticate on GCP
       uses: GoogleCloudPlatform/github-actions/setup-gcloud@master