Drop node 12, add node 18

Author: abraham

.github/workflows/index.yaml

@@ -10,7 +10,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        node: [12, 14, 16]
+        node: [14, 16, 18]
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3