[IPv6][SNMP]: Remove skip of IPv6 loopback testing

[SuvarnaMeenakshi]

Description of PR

Summary:
Fixes # (issue)

Type of change

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

Back port request

• 201911
• 202012
• 202205

Approach

What is the motivation for this PR?

SNMP over Loopback ipv6 is currently being skipped.
sonic-net/sonic-buildimage#15487 -fixes snmp over ipv6.
After the above fix, SNMP over Loopback and management should work.

How did you do it?

Remove skip of ipv6.

How did you verify/test it?

Test on vs testbed with single-asic image with sonic-buildimage 15487 fix.

 ./run_tests.sh -n vms-kvm-t0 -d vlab-01 -c snmp/test_snmp_loopback.py -f vtestbed.yaml -i ../ansible/veos_vtb -e "--skip_sanity --disable_loganalyzer" -u
 ..
 ---------------------------------------------------------------------------------------------------- generated xml file: /data/sonic-mgmt/tests/logs/tr.xml ----------------------------------------------------------------------------------------------------
============================================================================================================ 1 passed, 1 warnings in 25.73 seconds =============================================================================================================
INFO:root:Can not get Allure report URL. Please check logs

Prerequisite PRs:
sonic-net/sonic-buildimage#15688
sonic-net/sonic-buildimage#15487

Any platform specific information?

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

Documentation

[qiluo-msft]

# TODO: Fix snmp query over Management IPv6 adderess and add SNMP test over management IPv6 address.

Do you want to remove this TODO?
Do you want add mgmt in the PR title?

---

In reply to: 1622614016

---

Refers to: tests/snmp/test_snmp_loopback.py:56 in 384205c. [](commit_id = 384205c, deletion_comment = False)

[SuvarnaMeenakshi]

# TODO: Fix snmp query over Management IPv6 adderess and add SNMP test over management IPv6 address.

Do you want to remove this TODO? Do you want add mgmt in the PR title?

Refers to: tests/snmp/test_snmp_loopback.py:56 in 384205c. [](commit_id = 384205c, deletion_comment = False)

Removed comment.

This test specifically tests over loopback IPv4 and IPv6.
I will add another another test to test over mgmt ipv6 or explore enhancing one of the existing test cases to use both mgmt ipv4 and ipv6.

[SuvarnaMeenakshi]

@qiluo-msft can you review this.

[mssonicbld]

@SuvarnaMeenakshi PR conflicts with 202205 branch