Change get token behaviour to use certs only in when component is in cert auth only mode

[rrbadiani]

Description

There were 3 ways to get token oauth creds, ldap creds, certs only.

The conditions used to decide the method to Get token before this PR ->

if oauth is enabled we use oauth creds else if auth_mode is mtls then use certs to get a token else use ldap credentials

Now after this PR the logic to pick this method of getting a token will be

if oauth and not cert_auth_only then use oauth credentials else if auth_mode mtls or cert auth only then use certs else use ldap credentials

Fixes # (issue)

Type of change

• [ ] Bug fix (non-breaking change which fixes an issue)
• [X] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] This change requires a documentation update

How Has This Been Tested?

kraft zk

Checklist:

• [ ] Any variable/code changes have been validated to be backwards compatible (doesn't break upgrade)
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] If required, I have ensured the changes can be discovered by cp-ansible discovery codebase
• [ ] My code follows the style guidelines of this project
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] Any dependent changes have been merged and published in downstream modules

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[mansisinha]

Where are the kafka_connect_mds_cert_auth_only and similar variables defined for other cp components?

[rrbadiani]

kafka_connect_mds_cert_auth_only

they are already in 7.8.x code. this Pr is to use those variables to decide how we get the token. in the Earlier Pr they were used to skip defining the ldap client credentials on components but continued to use them in fetch the token.