Update lib/mediafire/util.js

lib/mediafire/util.js

@@ -1,7 +1,7 @@
 /**
  * @returns as a kilobit
  */
-export function parseFileSize (size: string): number {
+export function parseFileSize (size) {
     return parseFloat(size) * (
       /GB/i.test(size)
         ? 1000000