Add fabric monitoring commands.

[jfeng-arista]

What I did

Add a force option for config fabric port unisolate command.

Add a show command to display if a up link is get isolated or not . Example output is :

# show fabric isolation
asic0
  Local Link    Auto Isolated    Manual Isolated    Isolated
------------  ---------------  -----------------  ----------
           0                0                  0           0
           1                0                  0           0
           2                0                  0           0
....

Add test for the new commands. The test is failed now as it needs this https://github.com/sonic-net/sonic-swss/pull/3089 merged in first.

How I did it

How to verify it

Previous command output (if the output of a command-line utility has changed)

New command output (if the output of a command-line utility has changed)

[jfeng-arista]

the test failure needs this https://github.com/sonic-net/sonic-swss/pull/3089 merged in first. I could comment out failure test case for now, but that will cause the coverage check fail, let me know if we should leave this as is for now. thank you

[jfeng-arista]

@vmittal-msft @arlakshm

[arlakshm]

/Azp run Azure.sonic-utilities

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