[console][minigraph] Avoid generate config for self console port

[Blueve]

Why I did it

For MgmtTsToR device, it can manage 48/96 devices via console. Besides, it also have it own console port (console) which will be modeled in minigraph as a device serial link. Current code will generate configuration for it, but there are no change to do the reverse control and the configuration can lead confuse for users.

How I did it

Only generate console config for console ports which is in digital format.

How to verify it

Add new test data and existing unit test will cover this case.

test_minigraph_console_port (tests.test_minigraph_case.TestCfgGenCaseInsensitive) ... ok

Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006
• 202012

Description for the changelog

A picture of a cute animal (not mandatory but encouraged)

[Blueve]

Seems like the build pipeline is broken now

[lguohan]

please fix unit test error, it looks related your changes.

[Blueve]

please fix unit test error, it looks related your changes.

I am not seeing errors are related to my change...
The unit test for my change has passed: https://dev.azure.com/mssonic/build/_build/results?buildId=18602&view=logs&j=089762f3-bd71-59a9-4817-0f6c97173848&t=057cb327-2dfe-5d40-f7b7-1abf078516fc&l=990

I checked official build branch: https://sonic-jenkins.westus2.cloudapp.azure.com/job/vs/job/buildimage-vs-image/761/console
And it failed same test case as mine: https://dev.azure.com/mssonic/build/_build/results?buildId=18602&view=logs&jobId=0fb34b7e-bf5a-5901-643f-34f9ff251395&j=089762f3-bd71-59a9-4817-0f6c97173848&t=057cb327-2dfe-5d40-f7b7-1abf078516fc

A sample is: ERROR: test_bgpd_quagga (tests.test_j2files.TestJ2Files)

[Blueve]

/AZP run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).