fix(material): remove empty mat-prefix and mat-suffix (#2444)
fix(material): remove empty mat-prefix and mat-suffix (#2444)

fix #2443
ngx-formly/ngx-formly,ngx-formly/ngx-formly,formly-js/ng-formly,formly-js/ng-formly,ngx-formly/ngx-formly,ngx-formly/ngx-formly