Update Node.js version to 24 in unit-tests job

Agent-Logs-Url: https://github.com/shoptet/pr-test-coverage/sessions/49b0f45a-e0d5-4144-877e-ea60eaa9eb1a

Co-authored-by: simonjur <118170619+simonjur@users.noreply.github.com>

Author: Claude

.github/workflows/pr-check.yml

@@ -16,7 +16,7 @@ jobs:
       - name: Set up Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: '20'
+          node-version: '24'
 
       - name: Install dependencies
         run: npm ci