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The PR is intended to provide a fix for the change sonic-net/sonic-swss#1957

The old test behavior relies on a hardcoded max TC value of 255. Now it needs to be updated following the `SAI_SWITCH_ATTR_QOS_MAX_NUMBER_OF_TRAFFIC_CLASSES` attribute implementation in VS lib.

Due to the circular dependency, in order to have clean `sonic-sairedis` CI,
the current change should be merged first.

**DEPENDS:**
1. sonic-net/sonic-sairedis#1610

**What I did**
* Updated mirror VS test

**Why I did it**
* To align the behaviour with a new VS lib implementation

**How I verified it**
1. Run VS test
```
root@sonic: tests# pytest --dvsname=vs --log-cli-level=info -vvv test_mirror_port_span.py
======================================================================== test session starts =========================================================================
platform linux -- Python 3.8.10, pytest-7.1.2, pluggy-0.13.1 -- /usr/bin/python3
cachedir: .pytest_cache
rootdir: /root/work/debug/trim/asym/sonic-swss/tests
plugins: flaky-3.7.0
collected 10 items

test_mirror_port_span.py::TestMirror::test_PortMirrorQueue PASSED                                                                                              [ 10%]
test_mirror_port_span.py::TestMirror::test_PortMirrorAddRemove PASSED                                                                                          [ 20%]
test_mirror_port_span.py::TestMirror::test_PortMirrorMultiSpanAddRemove PASSED                                                                                 [ 30%]
test_mirror_port_span.py::TestMirror::test_PortMirrorPolicerAddRemove PASSED                                                                                   [ 40%]
test_mirror_port_span.py::TestMirror::test_PortMultiMirrorPolicerAddRemove PASSED                                                                              [ 50%]
test_mirror_port_span.py::TestMirror::test_LAGMirrorSpanAddRemove PASSED                                                                                       [ 60%]
test_mirror_port_span.py::TestMirror::test_PortMirrorPolicerWithAcl PASSED                                                                                     [ 70%]
test_mirror_port_span.py::TestMirror::test_PortMirrorLAGPortSpanAddRemove PASSED                                                                               [ 80%]
test_mirror_port_span.py::TestMirror::test_PortLAGMirrorUpdateLAG PASSED                                                                                       [ 90%]
test_mirror_port_span.py::test_nonflaky_dummy PASSED                                                                                                           [100%]
```

**Details if related**
* N/A

#### A picture of a cute animal (not mandatory but encouraged)
```
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   //////   ' \/ `   ---
  //// / // :    : ---
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//          //..\\
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             ''``
```