[tests] migrate to use common tf-run-example image

Author: danisla

tests/pipelines/tf-examples-gke-k8s-helm.yaml

@@ -63,7 +63,20 @@ jobs:
       params:
         subject: email/subject-failed
         body: email/body-failed
-    file: git/tests/tasks/run-example.yaml
+    config:
+      platform: linux
+      image_resource:
+        type: docker-image
+        source:
+          repository: gcr.io/cloud-solutions-group/tf-run-example
+          tag: latest
+      inputs:
+      - name: git
+      - name: git-pull-requests
+        optional: true
+      outputs:
+      - name: email
+      run: {path: /opt/run-example.sh}
 
 ###
 # Resource types

tests/pipelines/tf-examples-gke-multi-region.yaml

@@ -47,7 +47,20 @@ jobs:
       params:
         subject: email/subject-failed
         body: email/body-failed
-    file: git/tests/tasks/run-example.yaml
+    config:
+      platform: linux
+      image_resource:
+        type: docker-image
+        source:
+          repository: gcr.io/cloud-solutions-group/tf-run-example
+          tag: latest
+      inputs:
+      - name: git
+      - name: git-pull-requests
+        optional: true
+      outputs:
+      - name: email
+      run: {path: /opt/run-example.sh}
 
 ###
 # Resource types

tests/pipelines/tf-examples-gke-service-lb.yaml

@@ -45,7 +45,20 @@ jobs:
       params:
         subject: email/subject-failed
         body: email/body-failed
-    file: git/tests/tasks/run-example.yaml
+    config:
+      platform: linux
+      image_resource:
+        type: docker-image
+        source:
+          repository: gcr.io/cloud-solutions-group/tf-run-example
+          tag: latest
+      inputs:
+      - name: git
+      - name: git-pull-requests
+        optional: true
+      outputs:
+      - name: email
+      run: {path: /opt/run-example.sh}
 
 ###
 # Resource types