Proto/Client: update register key CLI with companion and consensus keys args

This MR adds companion-key and consensus-key as arguments for the register key as delegate client command:

octez-client register key <manager_key> as delegate --consensus-key <consensus_key> --companion-key <companion_key> 

instead of providing two additional client commands for setting companion keys:

octez-client register key <manager_key> as delegate with companion key <companion_key>
octez-client register key <manager_key> as delegate with consensus key <consensus_key> and companion key <companion_key>

The client command can also take proof-of-possession arguments for tz4 consensus and companion keys:

octez-client register key <manager_key> as delegate --consensus-key <consensus_key> --companion-key <companion_key> --consensus-key-pop <consensus_key_pop> --companion-key <companion_key>

Manually testing the MR

• launch sandbox and activate the alpha protocol

./src/bin_node/octez-sandboxed-node.sh 1 --connections 0
eval $(./src/bin_client/octez-init-sandboxed-client.sh 1)
octez-activate-alpha

• generate 3 keys: main, consensus and companion

octez-client gen keys main
octez-client gen keys consensus -s bls
octez-client gen keys companion -s bls
octez-client list known addresses

• fund the main account

octez-client --wait none transfer 3000000 from bootstrap2 to main --burn-cap 1
octez-client bake for --minimal-timestamp

• register main as delegate and set consensus as a consensus key and companion as a companion key

octez-client --wait none register key main as delegate --consensus-key consensus --companion-key companion
octez-client bake for --minimal-timestamp

• check that consensus and companion keys are pending keys for consensus_key and companion_key respectively

octez-client rpc get /chains/main/blocks/head/context/delegates/<main_pkh>

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR