ui: hide installation key if no extras key can be used

ModpackUpdater.Apps.Client/MainForm.cs

@@ -97,6 +97,8 @@ public partial class MainForm
         if (modpackInfo != null)
             features = new(updateConfig);
 
+        radTextBox_InstallKey.Visible = radLabel_InstallationKey.Visible = !string.IsNullOrWhiteSpace(updateConfig.UnleashApiUrl);
+
         if (modpackInfo == null || string.IsNullOrWhiteSpace(RadTextBox_MinecraftProfileFolder.Text) /*|| modpackInfo.Valid*/)
         {
             SetStatus(LangRes.StatusText_MinecraftProfileWarning, AppGlobals.Symbols.GetSvgImage(AppSymbols.general_warning_sign, SymbolSize.Small));
@@ -118,7 +120,6 @@ public partial class MainForm
             RadButton_Install.Enabled = false;
             return false;
         }
-
         RadButton_CheckForUpdates.Enabled = true;
         RadButton_Install.Enabled = true;
         return true;