[chassis][fabric][VoQ] Add tests to test fabric ports on chassis

[smaheshm]

Description

On a VoQ chassis fabric port information can be obtained from CLI on supervisor card. ASICs between line cards are connected to each other via the fabric ports.
Example test cases:

• Fabric port counters
• Link connectivity/reachability
• Link recovery in case of errors
• VoQ queue counters (should it be part of supervisor or line card?)

Steps to reproduce the issue:
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Describe the results you received:

Describe the results you expected:

Additional information you deem important:

**Output of `show version`:**

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**Attach debug file `sudo generate_dump`:**

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[vmittal-msft]

fabric port test plan under review -
#4305

[rlhui]

@kenneth-arista

[kenneth-arista]

Also see this PR: #6620

[wenyiz2021]

closing as tests added