Avoid fetching the default server every time when the user hasn't chosen one...

Avoid fetching the default server every time when the user hasn't chosen one by explicitly assigning the default value

app/src/main/java/com/frostnerd/smokescreen/util/preferences/DnsServerInformationPreference.kt

@@ -54,7 +54,9 @@ class DnsServerInformationPreference(key: String, defaultValue: (String) -> DnsS
             }
 
         } else {
-            defaultValue(key)
+            defaultValue(key).also {
+                setValue(thisRef, property, it)
+            }
         }
     }