Add engines.node field to package.json, matching winston

Author: DABH

package.json

@@ -46,5 +46,8 @@
     "nyc": "^15.1.0",
     "rimraf": "^5.0.5"
   },
-  "types": "./index.d.ts"
+  "types": "./index.d.ts",
+  "engines": {
+    "node": ">= 12.0.0"
+  }
 }