BREAKING: ci: drop node 12, add 18

Author: ungoldman

.github/workflows/tests.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        node: [12, 14, 16]
+        node: [14, 16, 18]
 
     steps:
       - uses: actions/checkout@v3