fix(typography): change display2 font size to correct value (#1652)

Resolves #1638

Author: mianuddin

packages/mdc-typography/_variables.scss

@@ -49,7 +49,7 @@ $mdc-typography-styles: (
     text-transform: inherit
   ),
   display2: (
-    font-size: 2.813rem, /* 45px */
+    font-size: 2.8125rem, /* 45px */
     line-height: 3rem, /* 48px */
     font-weight: map-get($mdc-typography-font-weight-values, regular),
     letter-spacing: normal,