Trigger setup-test-env job on default branch

Related issue: https://jihulab.com/gitlab-cn/gitlab/-/issues/2715

What does this MR do and why?

Trigger setup-test-env job on default branch,

to fix failed pipeline on pre-main-jh branch: https://jihulab.com/gitlab-cn/gitlab/-/pipelines/1965611

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Add new rule if: '$CI_COMMIT_REF_NAME == $CI_DEFAULT_BRANCH'

to setup-test-env job.

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