…ap] Use conditional sleep based on route scale (sonic-net#616)

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### Description of PR

Replaced the fixed 180-second sleep in `test_nhop_group_interface_flap` with a conditional wait based on the number of eBGP v4/v6 routes on the DUT.
- Retrieves eBGP v4 and v6 route counts via `get_ip_route_summary()`.
- Sleeps for:
 - **180 seconds** if v4 or v6 eBGP route count exceeds 10,000.
 - **20 seconds** otherwise.

Summary:
Fixes # (issue)
The current implementation applies a fixed time.sleep(180) only for chassis systems.
However, during nightly runs on disagg-T2 devices, we observed that they also require an increased timeout for route programming, similar to chassis platforms.
### Type of change

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- Fill x for your type of change.
- e.g.
- [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
- [ ] 202505

### Approach
#### What is the motivation for this PR?
Enhance the time.sleep logic to support additional platforms beyond chassis systems.
#### How did you do it?
Retrieve eBGP v4 and v6 route counts using get_ip_route_summary().
If either count exceeds 10,000, apply a 180-second sleep; otherwise, use a shorter delay.
#### How did you verify/test it?
Validated the change by running the test in the Microsoft lab.
#### Any platform specific information?

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

### Documentation
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(If it's a new feature, new test case)
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…c-net#5041)

Update the meta code to support DNAT Pool changes (sonic-net#616)
[syncd] Fix notification on shutdown request (sonic-net#637)
Advance the submodule head of SAI (sonic-net#641)

Signed-off-by: Stephen Sun <stephens@mellanox.com>

Update the meta code to support DNAT Pool changes (sonic-net#616)
[syncd] Fix notification on shutdown request (sonic-net#637)
Advance the submodule head of SAI (sonic-net#641)
Add new line in sai_meta_log_syncd fprintf call (sonic-net#649)
Fix Warmboot Issue when upgraded Image SAI return Switch Internal
OID not accounted in previous image. (sonic-net#654)