Parameterise execution of runner

Author: kpturner

action.yml

@@ -65,6 +65,11 @@ inputs:
     description: >-
       Directory that contains actions-runner software and scripts. E.g. /home/runner/actions-runner.
     required: false
+  run-runner-as-service:
+    type: boolean
+    description: >-
+      Start the runner as a service rather than using ./run.sh as root.
+    required: false
 outputs:
   label:
     description: >-