feat: direct link macsec changes

[sirijareddyibm]

PR summary

Fixes: Cloudbbs/planning#14588

PR Checklist

Please make sure that your PR fulfills the following requirements:

• The commit message follows the Angular Commit Message Guidelines.
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• New tests
• Build/CI related changes
• Documentation content changes
• Other (please describe)

What is the current behavior?

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

Other information

[sirijareddyibm]

Test results:

> python3 -m pytest test/integration/test_direct_link_v1_recent.py
=================================================== test session starts ====================================================
platform darwin -- Python 3.9.6, pytest-6.2.5, py-1.11.0, pluggy-1.5.0
rootdir: /Users/sirija/Desktop/repos/dl-macsec/networking-python-sdk
plugins: cov-2.12.1, rerunfailures-12.0
collected 1 item                                                                                                           

test/integration/test_direct_link_v1_recent.py .                                                                     [100%]

===================================================== warnings summary =====================================================
../../../../Library/Python/3.9/lib/python/site-packages/urllib3/__init__.py:35
  /Users/sirija/Library/Python/3.9/lib/python/site-packages/urllib3/__init__.py:35: NotOpenSSLWarning: urllib3 v2 only supports OpenSSL 1.1.1+, currently the 'ssl' module is compiled with 'LibreSSL 2.8.3'. See: https://github.com/urllib3/urllib3/issues/3020
    warnings.warn(

test/integration/test_direct_link_v1_recent.py::TestDirectLinkV1::test_gateway_macsec
  /Users/sirija/Library/Python/3.9/lib/python/site-packages/ibm_cloud_sdk_core/api_exception.py:56: DeprecationWarning: Using the `code` attribute on the `ApiException` is deprecated and will be removed in the future. Use `status_code` instead.
    warnings.warn(

-- Docs: https://docs.pytest.org/en/stable/warnings.html
======================================== 1 passed, 2 warnings in 190.26s (0:03:10) =========================================

[sridhargk]

LGTM