Use "CI_COMMIT_SHA" instead of "CI_COMMIT_BRANCH"

What does this MR do and why?

解决 Tag pipeline 的报错：https://jihulab.com/gitlab-cn/mono-client/-/jobs/9217696

error: CI_COMMIT_BRANCH: unbound variable

Why

CI_COMMIT_BRANCH 在 Tag 触发的 Pipeline 中不可用。

Screenshots or screen recordings

No UI changes.

How to set up and validate locally

经验证，修改后的 Tag pipeline 是可以正常工作的：

• Tag: test-tag-pipeline-2
• Pipeline: https://jihulab.com/gitlab-cn/mono-client/-/pipelines/1504231