refactor(VBtn): remove $el type
refactor(VBtn): remove $el type

Turns out it wasn't actually needed

Webifi/vuetify,vuetifyjs/vuetify,Webifi/vuetify,vuetifyjs/vuetify,Webifi/vuetify,Phlow2001/vuetify,vuetifyjs/vuetify,Phlow2001/vuetify,Phlow2001/vuetify,Phlow2001/vuetify,vuetifyjs/vuetify