Support for ZKRoutingDataWriter to forward write requests as HTTPS as part of MetadataStoreRouting

[GrantPSpencer]

Is your feature request related to a problem? Please describe.
We do not allow HTTP write requests (PUT, POST, DELETE) to our helix-rest deployments. When a HTTPS write request is made to helix-rest on the RoutingData (aka modifying a sharding key), if the request does not hit the ZK_ROUTING_DATA_WRITER_LEADER, then it will forward the request to the leader but as an HTTP request.

The current workaround is to directly resolve the curl request to the host that is the current ZK_ROUTING_DATA_WRITER_LEADER so that the request is not forward.

Relevant methods:
buildAndSendRequestToLeader

addMetadataStoreRealm

deleteMetadataStoreRealm

addShardingKey

deleteShardingKey

Describe the solution you'd like
If possible, the ZKRoutingDataWriter should possibly support forwarding as HTTPS if the original request was also via HTTPS.