enable test_link_down on t0 and t1 devices

[BYGX-wcr]

Description of PR

Summary: Fixes # (issue) 11671 This PR is used to enable the test_link_down script to test SONiC T0 and T1 devices. There was only one line of code change made to tests/platform_tests/test_link_down.py.

Type of change

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

Back port request

• [ ] 202012
• [ ] 202205
• [ ] 202305
• [ ] 202311
• [ ] 202405

Approach

What is the motivation for this PR?

Fill the test gap.

How did you do it?

Change the test script

How did you verify/test it?

I tested it on T0, T1 and T2 DUTs in Microsoft's internal testbed and the new script works fine.

Any platform specific information?

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

Documentation

[linux-foundation-easycla[bot]]

• :white_check_mark:login: BYGX-wcr / (d30705b47a2be65af3e2346a9bba3ab1ad45815d)

The committers listed above are authorized under a signed CLA.

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