chore: fix lint rumdl definition (#5679)

Author: remyleone

.github/workflows/lint.yml

@@ -60,6 +60,7 @@ jobs:
   rumdl:
     name: rumdl
     runs-on: "${{ vars.RUNS_ON || 'ubuntu-latest' }}"
+    steps:
       - name: Checkout
         uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
       - name: rumdl