Update porter_stack_stefantest-graviton.yml

Author: stefanmcshane

.github/workflows/porter_stack_stefantest-graviton.yml

@@ -5,7 +5,7 @@
 name: Deploy to stefan-testcachemultistep
 jobs:
   porter-deploy:
-    runs-on: ubicloud-standard-2-arm
+    runs-on: ubuntu-latest
     steps:
     - name: Checkout code
       uses: actions/checkout@v4