Include Node.js version 18 CI matrix test

Author: Borewit

.github/workflows/nodejs-ci.yml

@@ -47,7 +47,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [10.x, 12.x, 14.x, 16.x]
+        node-version: [10.x, 12.x, 14.x, 16.x, 18.x]
 
     steps: