Speed up GitHub action runs and save resources

- Require short running actions (golangci, test, build) before starting slower virtual-k8s-cluster and only run virtual-ocp when virtual-k8s-cluster succeed
- Allow cancellation

These two changes together reduce the amount of resources used

Signed-off-by: Sebastian Sch <sebassch@gmail.com>

.github/workflows/virtual-cluster.yml

@@ -1,8 +1,18 @@
 name: sriov-operator-test
-on: [pull_request]
+on:
+  workflow_run:
+    workflows: ["Go"]
+    types:
+      - completed
+
+concurrency:
+  group: ${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
 
 jobs:
   virtual-k8s-cluster:
+    if: ${{ github.event.workflow_run.conclusion == 'success' }}
+
     name: k8s
     runs-on: [sriov]
     steps:
@@ -24,6 +34,11 @@ jobs:
           path: ./artifacts.tar.gz
 
   virtual-ocp:
+    needs: [
+      virtual-k8s-cluster
+    ]
+    if: ${{ github.event.workflow_run.conclusion == 'success' }}
+
     name: ocp
     runs-on: [ ocp ]
     steps: