backlog user activities
backlog user activities <user-id> [flags]<user-id> <int>- ユーザー ID
-L,--limit <int>(default 20)- 取得件数
--activity-type <string>- アクティビティタイプ ID（カンマ区切り）
backlog user activities 12345backlog user activities 12345 --limit 50backlog user activities <user-id> [flags]<user-id> <int>-L, --limit <int> (default 20)--activity-type <string>backlog user activities 12345backlog user activities 12345 --limit 50