UI: Update minimum window size to 800x500 (#6425)

src/Ryujinx/UI/Windows/MainWindow.axaml

@@ -14,8 +14,8 @@
     WindowState="{Binding WindowState}"
     Width="{Binding WindowWidth}"
     Height="{Binding WindowHeight}"
-    MinWidth="1092"
-    MinHeight="672"
+    MinWidth="800"
+    MinHeight="500"
     d:DesignHeight="720"
     d:DesignWidth="1280"
     x:DataType="viewModels:MainWindowViewModel"