cleanup(stepper): remove unused class (#13006)
cleanup(stepper): remove unused class (#13006)

Fixes the stepper not setting the proper font size for custom number icons.

Fixes #12999.
Jefiozie/material2,angular/components,crisbeto/material2,DevVersion/material2,josephperrott/material2,josephperrott/material2,jelbourn/material2,crisbeto/material2,angular/components,crisbeto/material2,andrewseguin/material2,Jefiozie/material2,andrewseguin/material2,DevVersion/material2,josephperrott/material2,Jefiozie/material2,jelbourn/material2,angular/components,Jefiozie/material2,andrewseguin/material2,DevVersion/material2,Jefiozie/material2,mmalerba/material2,andrewseguin/material2,mmalerba/material2,mmalerba/material2,andrewseguin/material2,mmalerba/material2,crisbeto/material2,josephperrott/material2,jelbourn/material2,DevVersion/material2,angular/components,josephperrott/material2,mmalerba/material2,jelbourn/material2,jelbourn/material2,DevVersion/material2