fix(ci): define runs-on as string

.gitea/workflows/generate-readme.yaml

@@ -16,8 +16,7 @@ jobs:
   generate-parameters:
     container:
       image: docker.io/library/node:24.11.1-alpine
-    runs-on:
-    - ubuntu-latest
+    runs-on: ubuntu-latest
     steps:
     - name: Install tooling
       run: |