Set font-size of webfont icon inside a button (#2046)

.changeset/kind-days-sneeze.md

@@ -0,0 +1,5 @@
+---
+"@tabler/core": patch
+---
+
+Set `font-size` of an `i` element with `icon` class in a `button` element

src/scss/ui/_buttons.scss

@@ -23,6 +23,7 @@
     width: var(--#{$prefix}btn-icon-size);
     height: var(--#{$prefix}btn-icon-size);
     min-width: var(--#{$prefix}btn-icon-size);
+    font-size: var(--#{$prefix}btn-icon-size);
     margin: 0 calc(var(--#{$prefix}btn-padding-x) / 2) 0 calc(var(--#{$prefix}btn-padding-x) / -4);
     vertical-align: bottom;
     color: inherit;