chore (ci): add node v20 to build matrix

Author: alxndrsn

.github/workflows/ci.yml

@@ -40,6 +40,7 @@ jobs:
           - '14'
           - '16'
           - '18'
+          - '20'
         os:
           - ubuntu-latest
     name: Node.js ${{ matrix.node }} (${{ matrix.os }})