Update GH Actions jobs from Node 18 to 20.

Signed-off-by: Roland Grunberg <rgrunber@redhat.com>

Author: rgrunber

.github/workflows/pr-verify.yml

@@ -14,7 +14,7 @@ jobs:
       - name: Set Up NodeJS
         uses: actions/setup-node@v4
         with:
-          node-version: '18'
+          node-version: '20'
       - name: Set Up Java
         uses: actions/setup-java@v4
         with: