Fix test issue of the qos for the SPC4

[nhe-NV]

The headroom_overhead and extra_margin that aligned for 400G only applicable for the SPC3, for SPC4, need to do additional alignment.

Description of PR

Summary: Fixes # (issue)

Type of change

• [x] Bug fix
• [ ] Testbed and Framework(new/improvement)
• [ ] Test case(new/improvement)

Back port request

• [ ] 202012
• [ ] 202205
• [ ] 202305
• [x] 202311
• [x] 202405

Approach

What is the motivation for this PR?

How did you do it?

How did you verify/test it?

Any platform specific information?

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

Documentation