CI/CD Change/Requirements Dashboard

[wuhuizuo]

Changes

• also triggerBR integration testing when changes are made to DDL module. @BornChanger @Benjamin2037 #3039
• Add it.

Requirements

• tiflash integration test support feature branch #3041
• tidb ddl integration test support feature branch
• Add pipeline script url in the job description(not the build description).
• Refactor CI jobs for tikv/raft-engine #3205
• Add it.