Update servers_v7.json (#9367)

Good morning,

Compared to your recommendations, everything was done except 2 things:
I left the connection/disconnect message because I am logging this in my discord server (protected channel)

I left the maps at default, to see over time.

Thank's

servers_v7.json

@@ -259,5 +259,9 @@
   {
     "name": "SkyPlex",
     "address": ["mc-skyplex.net"]
+  },
+  {
+    "name": "Gadgetroch's Server",
+    "address": ["mindustry.gadgetroch.com", "mindustry.gadgetroch.com:6568"]
   }
 ]