fix(inkButton): md size icon not work

Author: xiaoland

packages/web-design/src/components/inkButton/inkButton.scss

@@ -71,15 +71,15 @@
   &--size-md {
     @include apply-font(label-lg);
 
-    :global(.ink-button__icon) {
+    .ink-button__icon {
       @include apply-icon(md);
     }
   }
 
   &--size-sm {
     @include apply-font(label-md);
 
-    :global(.ink-button__icon) {
+    .ink-button__icon {
       @include apply-icon(sm);
     }
   }