Fix test_syslog_source_ip issue

[JibinBao]

Description of PR

When removing mgmt vrf, sometimes dut connection will be lost for a while. So, before config reload we need to remove mgmt vrf, otherwise it will cause host unreachable.

Summary: Fixes # (issue)

Type of change

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

Back port request

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

Approach

What is the motivation for this PR?

Fix pytest_ansible.errors.AnsibleConnectionFailure: Host unreachable in the inventory in restore_config_by_config_reload

How did you do it?

Before config reload remove mgmt vrf

How did you verify/test it?

Run all test_syslog_source_ip case

Any platform specific information?

Any

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

Documentation

[JibinBao]

/azpw run Azure.sonic-mgmt

[mssonicbld]

/AzurePipelines run Azure.sonic-mgmt

[azure-pipelines[bot]]

Azure Pipelines successfully started running 1 pipeline(s).

[JibinBao]

/azpw run Azure.sonic-mgmt

[mssonicbld]

/AzurePipelines run Azure.sonic-mgmt

[azure-pipelines[bot]]

Azure Pipelines successfully started running 1 pipeline(s).

[bingwang-ms]

The test case was skipped because of issue https://github.com/sonic-net/sonic-mgmt/issues/6479. Will the issue be fixed by this PR?

[JibinBao]

The test case was skipped because of issue #6479. Will the issue be fixed by this PR?

No, for issue of https://github.com/sonic-net/sonic-mgmt/issues/6479, the fix is https://github.com/sonic-net/sonic-mgmt/pull/13280. Hi @StormLiangMS ,as what we discussed before, Can you close the issue https://github.com/sonic-net/sonic-mgmt/issues/6479?