fix: typo

Author: kazupon

src/i18n.ts

@@ -26,15 +26,15 @@ import { isEmptyObject } from './utils'
  * `I18nOptions` is inherited {@link ComposerOptions} and {@link VueI18nOptions}, so you can specify these options.
  *
  */
-export interface I18nAddtionalOptions {
+export interface I18nAdditionalOptions {
   /**
    * Whether vue-i18n legacy API use on your Vue App.
    * @defaultValue `false`
    */
   legacy?: boolean
 }
 
-export type I18nOptions = I18nAddtionalOptions &
+export type I18nOptions = I18nAdditionalOptions &
   (ComposerOptions | VueI18nOptions)
 
 /**