Filter checkmarks don't display properly when UIO line height changes

[cindyli]

Describe the bug

Filter checkmarks don't display properly when UIO line height changes.

To Reproduce

Steps to reproduce the behavior:

1. Go to the Views page, open the filter section, click a checkbox, a checkmark shows;
2. Open UIO, gradually increase the line height;
3. Check the position of the checkmark. It stays at the same position but the checkbox gradually moves down which causes the checkmark no longer displays in the checkbox.

Expected behavior

The checkmark should always stay inside of the checkbox it belongs to.

Screenshots

Additional context

Checkmarks are currently drawn using box-shadow and transform and displays using an absolute position. When the line height increases and contents adjust position accordingly, checkmarks stays in their absolution position and don't move along.

The solution is to replace the drawing method with content: '\2713';. \2713 is a css encoding for the checkmark symbol. Using content attribute will make checkmarks a part of the content, which will move along with other contents when the line height changes.