chore: Drop support for Node.js v8

BREAKING CHANGE:
Node.js version 10 or later is required (dropped support for v6 and v8)

Author: medikoo

package.json

@@ -55,5 +55,8 @@
       "tsx",
       "js"
     ]
+  },
+  "engines": {
+    "node": ">=10.0"
   }
 }