controller: fix the low_ru request missed (#8368)

[ti-chi-bot]

This is an automated cherry-pick of #8368

What problem does this PR solve?

Issue Number: Close #8349

What is changed and how does it work?

controller: fix the low_ru request missed 

The problem is that `c.run.currentRequests` is shared by all groups.
If one group triggers a token request that isn't handled by the response, the other group's requests will be discarded.
Here, we do not discard the low_ru triggers.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Release note

None.

[ti-chi-bot]

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This pull-request has been approved by: HuSharp, nolouch

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