maint: Update GitHub Actions workflow.

Author: thet

.github/workflows/test.yml

@@ -11,10 +11,10 @@ jobs:
     name: test
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
-    - uses: actions/setup-node@v3
+    - uses: actions/checkout@v4
+    - uses: actions/setup-node@v4
       with:
-        node-version: '18'
+        node-version: '20'
         cache: 'yarn'
     - run: |
         make install