Update .sr-only mixin and utility (#25197)

* Remove clip-path from .sr-only utility as it causes perf regressions in Chrome

* change snippet to example

scss/mixins/_screen-reader.scss

@@ -11,7 +11,6 @@
   overflow: hidden;
   clip: rect(0, 0, 0, 0);
   white-space: nowrap;
-  clip-path: inset(50%);
   border: 0;
 }
 
@@ -30,6 +29,5 @@
     overflow: visible;
     clip: auto;
     white-space: normal;
-    clip-path: none;
   }
 }