[Performance Analytics] Enable performance analytics on project page

User Story

1. As a user:

I want to see the branch selector on the Performance Analytics page.

So that I can filter the performance analysis data by branch name.

2. As a user:

I want to see the default branch name as the default selection of the branch selector.

So that I can see the default branch data when I first enter the page.

3. As a user:

I want to see the tooltip when I hover over the icon after the branch selector.

So that I can see the “分支选项仅影响代码提交次数和代码行数指标” as the tip text.

Mockup