fix(chips): chip remove icon isn't sized to match the spec (#10491)

- set `.md-chip-remove md-icon`'s `min-height` and `min-width`
  - to `$chip-delete-icon-size`
- fixes a regression in `v1.1.0` where the icon size increased

Fixes #9619

Author: batsauto

src/components/chips/chips.scss

@@ -129,6 +129,8 @@ $contact-chip-name-width: rem(12) !default;
       md-icon {
         height: $chip-delete-icon-size;
         width: $chip-delete-icon-size;
+        min-height: $chip-delete-icon-size;
+        min-width: $chip-delete-icon-size;
         position: absolute;
         top: 50%;
         left: 50%;