Re-order spec_helper for ee and jh

What does this MR do and why?

Adjust the load order of ee and jh spec_helper so that jh covers ee's tests.

Version 1:

The most primitive way of writing is that jh is loaded after ee.

Version 2:

Then swap the order in this commit: !86843 (diffs) The purpose here is to use prepend_mod in the rspec support files.

Version 3: (Current MR)

I find it is better to have jh load after ee.

• still can use prepend_mod in spec modules
• can override ce/ee spec modules through Ruby re-open
• can override ce/ee spec config

More details see: https://jihulab.com/gitlab-cn/gitlab/-/merge_requests/777

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cc JH EM @prajnamas