[KIP-1139] Add support for OAuth jwt-bearer grant type

[anchitj]

[confluent-cla-assistant[bot]]

:tada: All Contributor License Agreements have been signed. Ready to merge.
:white_check_mark: anchitj
_{Please push an empty commit if you would like to re-run the checks to verify CLA status for all contributors.}

[emasab]

Hi @anchitj could you sign the new CLA? Thank you again.

[anchitj]

Done @emasab