Update .gitlab-ci.yml file

.gitlab-ci.yml

@@ -16,7 +16,11 @@
 stages:          # List of stages for jobs, and their order of execution
   - execute
 
-execute-job:      # This job runs in the execute stage.
+execute-job:      # This job runs in the execute
+
+  # Only pickup runner with tag of shell
+  tags:
+    - shell
   stage: execute
   script:
     - echo "Execute application..."