Bump actions/setup-node from 6.3.0 to 6.4.0

Bumps [actions/setup-node](https://github.com/actions/setup-node) from 6.3.0 to 6.4.0.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](actions/setup-node@v6.3.0...v6.4.0)

---
updated-dependencies:
- dependency-name: actions/setup-node
  dependency-version: 6.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -31,7 +31,7 @@ jobs:
       - name: Install dependent libraries
         run: sudo apt-get update && sudo apt-get install libpq-dev diffoscope
       - name: Set up Node
-        uses: actions/setup-node@v6.3.0
+        uses: actions/setup-node@v6.4.0
         with:
           node-version: 15
       - name: Set up Ruby