_sizing.scss in font-awesome-sass-6.1.0

- old
+ new

@@ -9,8 +9,8 @@
 }
 
 // step-based scale (with alignment)
 @each $size, $value in $fa-sizes {
   .#{$fa-css-prefix}-#{$size} {
-     @include fa-size($value);
+    @include fa-size($value);
   }
 }