chore: fix update-nodejs-versions workflow (#3904)

A robot told me this would fix [these
issues](https://github.com/bazel-contrib/rules_nodejs/actions/runs/22607491947/job/65502627549#step:6:41)
because:

Two changes:
  - actions/setup-node@v2 → v4 (v2 is very old)
- peter-evans/create-pull-request@v3 → v7 — v3 sets the Authorization
header directly, which conflicts with actions/checkout@v6's new
includeIf-based credential injection,
  causing the "Duplicate header" 400 error

Author: jbedard

.github/workflows/update-nodejs-versions.yml

@@ -24,14 +24,14 @@ jobs:
           fetch-depth: 0
 
       - name: Setup Node.js
-        uses: actions/setup-node@v2
+        uses: actions/setup-node@v4
         with:
-          node-version: "14.x"
+          node-version: "lts/*"
       - uses: pnpm/action-setup@v4
       - run: npm run update-nodejs-versions
 
       - name: Create Pull Request
-        uses: peter-evans/create-pull-request@v3
+        uses: peter-evans/create-pull-request@v7
         with:
           token: ${{ secrets.PAT }}
           commit-message: Update Node.js Versions