docs: update the list of supported Node.js versions

The server uses `timeout.refresh()` (see [1]), which was added in Node.js 10.2.0.

Reference: https://nodejs.org/api/timers.html#timeoutrefresh

Related: #686

[1]: 37474c7

package.json

@@ -79,6 +79,6 @@
     "wrapper.mjs"
   ],
   "engines": {
-    "node": ">=10.0.0"
+    "node": ">=10.2.0"
   }
 }