[server] remove unused JWT-related flags

As it turns out, the following JWT flags aren't used in the code at all:
  * --jwks_discovery_endpoint_base
  * --jwt_allow_without_tls
  * --jwt_validate_signature

This patches removes the definitions of the flags and their usage
in a few tests.

Change-Id: Ib8e688b7c89e24cb5e91f6b6cc89b7ae984b4c35
Reviewed-on: http://gerrit.cloudera.org:8080/19891
Tested-by: Alexey Serbin <alexey@apache.org>
Reviewed-by: Yingchun Lai <laiyingchun@apache.org>
2 files changed