Fix CI workflow: use .nvmrc for Node version and pin setup-python to commit SHA

- Changed node-version from env.NODE_VERSION to node-version-file: '.nvmrc' to match other jobs
- Pinned actions/setup-python@v5 to commit SHA a26af69be951a213d495a4c3e4e4022e16d87065 for supply-chain security

Co-Authored-By: Filip Pyrek <[email protected]>

Author: devin-ai-integration[bot]

.github/workflows/ci.yml

@@ -159,12 +159,12 @@ jobs:
         uses: actions/setup-node@a0853c24544627f65ddf259abe73b1d18a591444 # v5
         with:
           cache: 'npm'
-          node-version: ${{ env.NODE_VERSION }}
+          node-version-file: '.nvmrc'
           registry-url: 'https://npm.pkg.github.com'
           scope: '@deepnote'
 
       - name: Setup Python
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5
         with:
           python-version: '3.12'