ci: only build on node 18+

Author: realnimish

.github/workflows/main.yml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        node: ['16.x', '18.x']
+        node: ['18.x']
         os: [ubuntu-latest]
 
     steps: