update workflows to use v4

Author: JamesHeppell

.github/workflows/ci.yml

@@ -4,10 +4,10 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/setup-node@v1
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
         with:
-          node-version: 18
+          node-version: 20
       - run: |
           npm install
           npm run lint