Composite Action to activate SA in GitHub Actions Runners (#24626)

* Adding composite action for service account activation

* Adding composite action for service account activation

* Adding an always condition to the key removal step

Co-authored-by: Elias Segundo <elias.segundo@luisrazo.local>

.github/actions/activate-service-account/action.yml

@@ -0,0 +1,22 @@
+name: "Activate Service Account"
+description: Setup a Service account with the key provided in base64 as an input
+inputs:
+  GCP_SERVICE_ACCOUNT:
+    description: Service account to activate in base64 format
+    required: true
+
+runs:
+  using: composite
+  steps:
+    - name: Setup GCP account
+      env:
+        SA_KEY_CONTENT: ${{inputs.GCP_SERVICE_ACCOUNT}}
+      shell: bash
+      run: |
+       echo "$SA_KEY_CONTENT" | base64 -d > /tmp/gcp_access.json
+       gcloud auth activate-service-account --key-file="/tmp/gcp_access.json" --no-user-output-enabled
+       gcloud auth configure-docker -q --no-user-output-enabled >& /dev/null
+    - name: Removing Keyfile
+      if: ${{ always() }}
+      shell: bash
+      run: rm -f /tmp/gcp_access.json