migrate apply_tags tekton task

Author: jotak

.tekton/pipeline-ref.yaml

@@ -458,8 +458,10 @@ spec:
       - "false"
   - name: apply-tags
     params:
-    - name: IMAGE
+    - name: IMAGE_URL
       value: $(tasks.build-image-index.results.IMAGE_URL)
+    - name: IMAGE_DIGEST
+      value: $(tasks.build-image-index.results.IMAGE_DIGEST)
     runAfter:
     - build-image-index
     taskRef: