dns: call handle.setServers() with a valid array

`handle.setServers()` takes an array, not a string.

PR-URL: https://github.com/nodejs/node/pull/50811
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>

lib/internal/dns/utils.js

@@ -2,7 +2,6 @@
 
 const {
   ArrayPrototypeForEach,
-  ArrayPrototypeJoin,
   ArrayPrototypeMap,
   ArrayPrototypePush,
   FunctionPrototypeBind,
@@ -143,12 +142,15 @@ class ResolverBase {
   }
 
   [kSetServersInteral](newSet, servers) {
-    const orig = this._handle.getServers() || [];
+    const orig = ArrayPrototypeMap(this._handle.getServers() || [], (val) => {
+      val.unshift(isIP(val[0]));
+      return val;
+    });
     const errorNumber = this._handle.setServers(newSet);
 
     if (errorNumber !== 0) {
       // Reset the servers to the old servers, because ares probably unset them.
-      this._handle.setServers(ArrayPrototypeJoin(orig, ','));
+      this._handle.setServers(orig);
       const { strerror } = lazyBinding();
       const err = strerror(errorNumber);
       throw new ERR_DNS_SET_SERVERS_FAILED(err, servers);