refactor(avatar): remove unused code (#15153)

Author: SisIvanova

projects/igniteui-angular/src/lib/core/styles/components/avatar/_avatar-theme.scss

@@ -68,23 +68,7 @@
     @include css-vars($theme);
 
     $variant: map.get($theme, '_meta', 'variant');
-    $bootstrap-theme: $variant == 'bootstrap';
-    $box-shadow: map.get((
-        'material': null,
-        'fluent': null,
-        'bootstrap': 0 0 0 rem(3px) var-get($theme, 'background'),
-        'indigo': null,
-    ), $variant);
-
-    %igx-avatar-outline {
-        position: absolute;
-        content: '';
-        width: 100%;
-        height: 100%;
-        border-radius: inherit;
-        opacity: .5;
-    }
-
+ 
     %igx-avatar-display {
         @include sizable();
 
@@ -114,20 +98,6 @@
                 --component-size: 1;
             }
         }
-
-        &::after {
-            box-shadow: none;
-
-            @if $bootstrap-theme {
-                @extend %igx-avatar-outline;
-            }
-
-            transition: box-shadow .15s $in-out-quad;
-        }
-
-        &:focus::after {
-            box-shadow: $box-shadow;
-        }
     }
 
     %igx-avatar-image {