fixup! fix(material/progress-spinner): fix build failures after rebase

Author: wagnermaciel

src/material-experimental/_index.scss

@@ -17,8 +17,5 @@
 // MDC-related themes
 @forward './mdc-core/core-theme' as mdc-core-* show mdc-core-theme, mdc-core-color,
   mdc-core-density, mdc-core-typography;
-@forward './mdc-progress-spinner/progress-spinner-theme' as mdc-progress-spinner-* show
-  mdc-progress-spinner-color, mdc-progress-spinner-typography, mdc-progress-spinner-density,
-  mdc-progress-spinner-theme;
 
 // Additional public APIs for individual components