refactor(textfield): add supporting-text-type token to filled text field

PiperOrigin-RevId: 511445103

Author: material-web-copybara

packages/mdc-textfield/_filled-text-field-theme.scss

@@ -126,6 +126,7 @@ $_light-theme: (
   supporting-text-size: null,
   supporting-text-tracking: null,
   supporting-text-weight: null,
+  supporting-text-type: null,
   trailing-icon-color: null,
   trailing-icon-size: null,
 );