Loading Dialog should have surface background

Signed-off-by: Andy Scherzinger <info@andy-scherzinger.de>

app/src/main/java/com/owncloud/android/ui/dialog/LoadingDialog.kt

@@ -54,7 +54,7 @@ class LoadingDialog : DialogFragment(), Injectable {
             viewThemeUtils?.platform?.tintDrawable(requireContext(), loadingDrawable)
         }
 
-        viewThemeUtils?.platform?.colorViewBackground(binding.loadingLayout, ColorRole.SURFACE_VARIANT)
+        viewThemeUtils?.platform?.colorViewBackground(binding.loadingLayout, ColorRole.SURFACE)
 
         return binding.root
     }