Add node 20.x test

Author: t2t2

.github/workflows/build.yml

@@ -42,7 +42,7 @@ jobs:
       fail-fast: false
       matrix:
         # See supported Node.js release schedule at https://nodejs.org/en/about/releases/
-        node-version: [14.x, 16.x, 18.x]
+        node-version: [14.x, 16.x, 18.x, 20.x]
 
     steps:
       - uses: actions/checkout@v3