Summary:
Cert upload was broken by FIPS changes. Basically, we're getting classcastexception right now.
Fixing it.

Original diff: https://phorge.dev.yugabyte.com/D54737

Test Plan: Tested uploading the cert/key pair manually. pair was generated according to the instructions in the docs.

Reviewers: dshubin, anijhawan

Reviewed By: anijhawan

Subscribers: yugaware, anijhawan

Differential Revision: https://phorge.dev.yugabyte.com/D54765