[vs][mirror]: Update test to use the max TC number provided by VS lib

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

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```

Author: mssonicbld

tests/test_mirror_port_span.py

@@ -40,19 +40,19 @@ def test_PortMirrorQueue(self, dvs, testlog):
 
         # Sub Test 2
         marker = dvs.add_log_marker()
-        self.dvs_mirror.create_span_session(session, dst_port, src_ports, direction="RX", queue="254")
+        self.dvs_mirror.create_span_session(session, dst_port, src_ports, direction="RX", queue="15")
         self.dvs_mirror.verify_session_status(session)
         self.dvs_mirror.remove_mirror_session(session)
         self.dvs_mirror.verify_no_mirror()
-        self.check_syslog(dvs, marker, "Failed to get valid queue 254", 0)
+        self.check_syslog(dvs, marker, "Failed to get valid queue 15", 0)
 
         # Sub Test 3
         marker = dvs.add_log_marker()
-        self.dvs_mirror.create_span_session(session, dst_port, src_ports, direction="TX", queue="255")
+        self.dvs_mirror.create_span_session(session, dst_port, src_ports, direction="TX", queue="16")
         self.dvs_mirror.verify_session_status(session, expected=0)
         self.dvs_mirror.remove_mirror_session(session)
         self.dvs_mirror.verify_no_mirror()
-        self.check_syslog(dvs, marker, "Failed to get valid queue 255", 1)
+        self.check_syslog(dvs, marker, "Failed to get valid queue 16", 1)
 
 
     def test_PortMirrorAddRemove(self, dvs, testlog):