Fix insufficient contrast for PropertyGrid dropdown text in Dark Mode#14152

LeafShi1 wants to merge 1 commit intodotnet:maindotnet/winforms:mainfrom

LeafShi1:Issue_14120_Update_DesignBinding_-to_use_correct_themeLeafShi1/winforms:Issue_14120_Update_DesignBinding_-to_use_correct_themeCopy head branch name to clipboard