docs: Update link in GroupSummaryResponse

The links in types.ts are all pointing to the English version except
the one in the GroupSummaryResponse type. This commit fixes that.

Author: Gasol

lib/types.ts

@@ -2829,7 +2829,7 @@ export type VerifyIDToken = {
 /**
  * Response body of get group summary.
  *
- * @see [Get group summary](https://developers.line.biz/ja/reference/messaging-api/#get-group-summary)
+ * @see [Get group summary](https://developers.line.biz/en/reference/messaging-api/#get-group-summary)
  */
 export type GroupSummaryResponse = {
   groupId: string;