Update qos sai due to no lossless pg for some platforms

[JibinBao]

Description of PR

1. For spc4 and above, there is only the lossy buffer, so the buffer for the lossless buffer will be taken by the lossy buffer. If the packet size is too small, the packet number sent to occupy the shared buffer will increase a lot, which will lead to the descriptor being exhausted, so update testQosSaiPgSharedWatermark, testQosSaiQSharedWatermark, and testQosSaiLossyQueue accordingly.
2. Remove the test config of scheduler.block_data_plane, otherwise it might raise yang validation error when do config reload
3. When there is no lossless buffer, return a dump buffer lossless pg profile, and skip tests related to lossless buffer case dynamically
4. Skip fixture reaseAllports for mellanox device, because after qos test is finished, the teardown will do config reload, it will restore the config of ports, we don't need this fixture before running tests. Also it can save 2 minutes
5. list the relevant Prs:
   [Mellanox] Update buffer calculations for Mellanox-SN5600-C224O8 SKU sonic-net/sonic-buildimage#20992
   [Mellanox] Add x86_64-nvidia_sn5610n-r0 new platform and SKUs sonic-net/sonic-buildimage#21056
   [Mellanox] Update Mellanox-SN5600-C256S1 buffer calculations sonic-net/sonic-buildimage#20991
   [Mellanox] Add x86_64-nvidia_sn5610n-r0 new platform and SKUs sonic-net/sonic-buildimage#21056
   [Mellanox] Update Mellanox-SN5600-C256S1, Mellanox-SN5600-C224O8 buffers and DSCP mapping sonic-net/sonic-buildimage#21427
   [Mellanox] Add x86_64-nvidia_sn5610n-r0 new platform and SKUs sonic-net/sonic-buildimage#21056
   [Mellanox] Update DSCP mapping for SN5600, SN5610 SKUs sonic-net/sonic-buildimage#21762

Summary:
Fixes # (issue)

Type of change

• Bug fix
• Testbed and Framework(new/improvement)
• New Test case
  • Skipped for non-supported platforms
  • Add ownership here(Microsft required only)
• Test case improvement

Back port request

• 202012
• 202205
• 202305
• 202311
• 202405
• 202411

Approach

What is the motivation for this PR?

update the qos sai test for no pg lossless buffer platform

How did you do it?

update for lossy case and skip test relatd to pg buffer lossless

How did you verify/test it?

Run qos sai test on platform without pg lossless buffer plaform

Any platform specific information?

sn5600 and sn5610

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

Documentation

[JibinBao]

cherry-pick from sonic-net/sonic-mgmt#16440