ENGCOM-4530: When setting \background\ for labels explicitly the labels in admin will #21825

 - Merge Pull Request #21825 from TomashKhamlai/magento2:minor-ui-regression-fix
 - Merged commits:
   1. 8b0318e

Author: magento-engcom-team

app/design/adminhtml/Magento/backend/web/css/source/forms/_fields.less

@@ -545,7 +545,6 @@
             & > .admin__field-label {
                 #mix-grid .column(@field-label-grid__column, @field-grid__columns);
                 cursor: pointer;
-                background: @color-white;
                 left: 0;
                 position: absolute;
                 top: 0;