Merge pull request #683 from puppetlabs/maint-remove_runs_on_input

(maint) - remove `runs_on` input from integration job

Author: GSPatton

.github/workflows/nightly.yml

@@ -20,7 +20,5 @@ jobs:
     secrets: "inherit"
 
   Integration:
-    needs: Acceptance
+    needs: Spec
     uses: "./.github/workflows/integration_test.yml"
-    with:
-      runs_on: "ubuntu-20.04"