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### Description of PR
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Summary: Splitting the packet trimming tests into symmetric and asymmetric
Fixes #
The packet trimming feature supports symmetric mode and asymmetric mode. Currently both mode cases in the same file. Need split them, this will greatly help us see where are we for all the features to be landed.

### Type of change

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- [x] Bug fix
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- [ ] Bug fix
- [ ] Testbed and Framework(new/improvement)
- [ ] New Test case
    - [ ] Skipped for non-supported platforms
- [x] Test case improvement

### Back port request
- [ ] 202205
- [ ] 202305
- [ ] 202311
- [ ] 202405
- [ ] 202411
- [x] 202505

### Approach
#### What is the motivation for this PR?

#### How did you do it?
Split case

#### How did you verify/test it?
Run regression locally, pass

#### Any platform specific information?

#### Supported testbed topology if it's a new test case?

### Documentation
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