Update scss mixins to comply with scss-linting rules (#22151)

* Fixed some linting issues

* Run npm tasks after scss cleanup

* Revert "Run npm tasks after scss cleanup"

This reverts commit 1103a0da68.

* Property sort order for grid

* Let's respest the property order in the mixins

* Respect property sort order in reboot file

* ::-ms-expand is a vendor-prefix, add it to the scss-lint disable

* Revert hover mixin comment

* Fixed missing mixin hover-focus

scss/mixins/_list-group.scss

@@ -6,6 +6,7 @@
     background-color: $background;
   }
 
+  //scss-lint:disable QualifyingElement
   a.list-group-item-#{$state},
   button.list-group-item-#{$state} {
     color: $color;
@@ -21,4 +22,5 @@
       border-color: $color;
     }
   }
+  // scss-lint:enable QualifyingElement
 }