Delete identity altogether when deleting a user

2. What is the nature and description of the request?

We can cause less confusion when customer deletes a user in identity provider. Now the problem is, if user01 logins the cluster once and we re-add the user01 in identity provider, if we don't delete the identity the user01 will never be able to login to the cluster. 

3. Why does the customer need this? (List the business requirements here)

This will make deleting user simple without deleting the identity again

4. List any affected packages or components.

Authentication