Fix 1.4 changelog

[deepakkinni]

What this PR does / why we need it: Adding 1.4.3 release notes on main

Which issue(s) this PR fixes: Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

[svcbot-qecnsdp]

Sorry, some of the pre-check tests are failing for this PR !

Please check the Jenkins job for more details https://container-dp.svc.eng.vmware.com/job/CNSDP-CI/798/

[xing-yang]

/approve