[Performance Analytics] Api for 'group' KPI card

group level input params:

• project_ids (Only support default branch)
• date range (max: 180 days)

project level input params:

• branch_name
• date range

output response:

• issues_closed 完成议题数
• commits_pushed 代码提交次数
• merge_requests_merged 已合并的MR数
• commits_per_pushed 人均代码提交次数