Update CI configuration

The Github CI workflow is a bit out of date.

- Update the cache action to v4.
- Use the latest LTS of Node.

Author: t27duck

.github/workflows/ci.yml

@@ -9,13 +9,13 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v2
         with:
-          node-version: '12'
-      - uses: actions/cache@v2
+          node-version: '22'
+      - uses: actions/cache@v4
         with:
           path: node_modules
           key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
       - run: yarn install
       - name: Lint
         run: yarn lint
       - name: Test
-        run: yarn test
+        run: yarn test