Update GitHub actions node version

Author: kddnewton

.github/workflows/main.yml

@@ -40,7 +40,7 @@ jobs:
       - uses: actions/checkout@master
       - uses: actions/setup-node@v4
         with:
-          node-version: 18.x
+          node-version: 20.x
           cache: yarn
       - uses: ruby/setup-ruby@v1
         with: