feat(ci): broaden usage of fast-startup ubuntu-slim runner (#43477)

Signed-off-by: hainenber <dotronghai96@gmail.com>

.github/workflows/github-action-validator.yml

@@ -19,7 +19,7 @@ concurrency:
 
 jobs:
   validate-all-ghas:
-    runs-on: ubuntu-26.04
+    runs-on: ubuntu-26.04 # Don't switch to ubuntu-slim as zizmore-action requires Docker
     permissions:
       contents: read
       # Required for the zizmor action to upload its SARIF results to
@@ -34,7 +34,7 @@ jobs:
       - name: Set up Node.js
         uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
         with:
-          node-version: "20"
+          node-version-file: "./superset-frontend/.nvmrc"
 
       - name: Install Dependencies
         # Versions are pinned to avoid ad-hoc, unpinned package installs.