Add a link to HashiCorp vault operator resource

[akshaykarle]

Change Description

This change allows presidio users to integrate with HashiCorp Vault using a python library.

Issue reference

N/A

Checklist

• [x ] I have reviewed the contribution guidelines
• I have signed the CLA (if required)
• My code includes unit tests
• All unit tests and lint checks pass locally
• [x ] My PR contains documentation updates / additions if required

[omri374]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[omri374]

Thanks! the HashiCorp vault operator looks great