Change key name to standard

.github/workflows/create-ami.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     env:
       STACK_NAME: joystream-github-action-${{ github.run_number }}
-      KEY_NAME: anuj-key
+      KEY_NAME: joystream-github-action-key
     steps:
     - name: Extract branch name
       shell: bash