Fix button focus on firefox tu use native focus

Author: cedric07

src/scss/03-base/_normalize.scss

@@ -211,17 +211,6 @@ button::-moz-focus-inner,
 	border-style: none;
 }
 
-/**
- * Restore the focus styles unset by the previous rule.
- */
-
-button:-moz-focusring,
-[type="button"]:-moz-focusring,
-[type="reset"]:-moz-focusring,
-[type="submit"]:-moz-focusring {
-	outline: 1px dotted ButtonText;
-}
-
 /**
  * Correct the padding in Firefox.
  */