[lag_member] add necessary missed imports to test

[AntonHryshchuk]

Description of PR

Summary:
During movement test to Python 3 (#14944), were deleted necessary imports of fixtures with "autouse=True":
copy_ptftests_directory
copy_arp_responder_py

copy_arp_responder_py:
The fixture copied required configuration files. The arp responder configurations used in the test by method setup_arp_responder
Error from test without this fixture:

failed = True
changed = True
end = 2024-12-11 05:18:59.588230
cmd = supervisorctl restart arp_responder
delta = 0:00:02.249219
rc = 7
invocation = {'module_args': {'creates': None, 'executable': None, '_uses_shell': True, 'strip_empty_ends': True, '_raw_params': 'supervisorctl restart arp_responder', 'removes': None, 'argv': None, 'warn': False, 'chdir': None, 'stdin_add_newline': True, 'stdin': None}}
start = 2024-12-11 05:18:57.339011
msg = non-zero return code
_ansible_no_log = None
stdout =
arp_responder: ERROR (not running)
arp_responder: ERROR (spawn error)stderr =

cmd supervisorctl restart arp_responder called in sonic-mgmt/tests/pc/test_lag_member.py: line 225

copy_ptftests_directory:
Error from test without this fixture:

cmd = /root/env-python3/bin/ptf --test-dir acstests/py3 lag_test.LagMemberTrafficTest --platform-dir /root/ptftests --platform remote -t 'dut_mac='"'"'9c:05:91:99:26:00'"'"';dut_vlan={'"'"'id'"'"': 109, '"'"'ip'"'"': '"'"'192.168.9.1/24'"'"'};ptf_lag={'"'"'port_list'"'"': ['"'"'eth1'"'"', '"'"'eth2'"'"', '"'"'eth3'"'"', '"'"'eth8'"'"', '"'"'eth9'"'"', '"'"'eth10'"'"', '"'"'eth11'"'"', '"'"'eth56'"'"'], '"'"'ip'"'"': '"'"'192.168.9.2/24'"'"'};port_not_behind_lag={'"'"'port_id'"'"': 16, '"'"'port_name'"'"': '"'"'eth16'"'"', '"'"'ip'"'"': '"'"'192.168.9.3/24'"'"'};kvm_support=True' --relax --debug info
delta = 0:00:00.433834
rc = 1
invocation = {'module_args': {'creates': None, 'executable': None, 'chdir': '/root', 'strip_empty_ends': True, '_raw_params': '/root/env-python3/bin/ptf --test-dir acstests/py3 lag_test.LagMemberTrafficTest --platform-dir /root/ptftests --platform remote -t \'dut_mac=\'"\'"\'9c:05:91:99:26:00\'"\......}
start = 2024-12-11 14:33:11.478026
msg = non-zero return code
_ansible_no_log = None
stdout =
Using packet manipulation module: ptf.packet_scapystderr =
Traceback (most recent call last):
  File "/root/env-python3/bin/ptf", line 820, in <module>
    platform_mod = import_module(config["platform_dir"], platform_name)
  File "/root/env-python3/bin/ptf", line 112, in import_module
    return module_specs.loader.load_module()
AttributeError: 'NoneType' object has no attribute 'loader'

Only when the test is executed with these imports does it pass.

Type of change

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

Back port request

• 202012
• 202205
• 202305
• 202311
• 202405

Approach

What is the motivation for this PR?

Stabilaze lag_member test

How did you do it?

Added removed imports

How did you verify/test it?

Executed on setup

Any platform specific information?

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

Documentation

[mssonicbld]

/azp run

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[AntonHryshchuk]

/azp run

[azure-pipelines]

Commenter does not have sufficient privileges for PR 16021 in repo sonic-net/sonic-mgmt

[AharonMalkin]

/azpw run

[azure-pipelines]

Commenter does not have sufficient privileges for PR 16021 in repo sonic-net/sonic-mgmt

[AntonHryshchuk]

/azpw run

[mssonicbld]

/AzurePipelines run

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[AntonHryshchuk]

/azpw run

[mssonicbld]

/AzurePipelines run

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Azure Pipelines successfully started running 1 pipeline(s).

[AntonHryshchuk]

/azpw run

[mssonicbld]

/AzurePipelines run

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Azure Pipelines successfully started running 1 pipeline(s).

[liat-grozovik]

@AntonHryshchuk to which branches this fix should get in?

[AntonHryshchuk]

@liat-grozovik
the root change was introduced only to master - #14944
But already created 202411 from master. We also need it in 202411

[mssonicbld]

Cherry-pick PR to 202411: #16990