Update actions/setup-node action to v6 (#1457)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/validate-openapi-spec.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
-      - uses: actions/setup-node@v5
+      - uses: actions/setup-node@v6
         with:
           node-version: '22'
       - name: Install our tools