fix: add missing tokens for Button component (openedx#1924)

scss/core/css/utility-classes.css

@@ -1,7 +1,7 @@
 /**
  * IMPORTANT: This file is the result of assembling design tokens
  * Do not edit directly
- * Generated on Tue, 31 Jan 2023 09:38:46 GMT
+ * Generated on Wed, 15 Feb 2023 14:44:39 GMT
  */
 
 .bg-dark {

src/Button/_mixins.scss

@@ -12,52 +12,3 @@
   // Manually declare to provide an override to the browser default
   @include border-radius($border-radius, 0);
 }
-
-// ------------------------
-// BELOW ARE EDX EXTENSIONS
-// ------------------------
-@mixin button-focus($ring-color) {
-  &.focus,
-  &:focus {
-    position: relative;
-    outline: 0;
-    box-shadow: none;
-
-    $distance: calc(#{$btn-focus-width} + #{$btn-focus-gap});
-    $distance-include-btn-border: calc(#{$distance} + #{$btn-border-width});
-
-    &::before {
-      content: "";
-      position: absolute;
-      top: calc(#{$distance-include-btn-border} * -1);
-      right: calc(#{$distance-include-btn-border} * -1);
-      bottom: calc(#{$distance-include-btn-border} * -1);
-      left: calc(#{$distance-include-btn-border} * -1);
-      border: solid $btn-focus-width $ring-color;
-      border-radius: calc(#{$btn-border-radius} + #{$distance});
-    }
-
-    &.btn-lg::before {
-      border-radius: calc(#{$btn-border-radius-lg} + #{$distance});
-    }
-
-    &.btn-sm::before {
-      border-radius: calc(#{$btn-border-radius-sm} + #{$distance});
-    }
-
-    &:active,
-    &.active {
-      &::before {
-        opacity: .75;
-      }
-    }
-
-    // Disabled buttons should not have focus rings
-    &:disabled,
-    &.disabled {
-      &::before {
-        display: none;
-      }
-    }
-  }
-}