Used to add a new seed to the system. You can provide empty
coin, the system will use that seed for all coins.
Allowed only for the "admin" role.
List of possible error codes:
-  REQUIRED
- Validation error that indicates which fields are required.
Provide required field(s).
-  UNSUPPORTED_COIN
- Indicates that the system does not support the coin
-  COIN_ALREADY_HAS_SEED
- It means you already add a seed for the coin
-  INVALID_MNEMONIC_PHRASE
- Indicates that the mnemonic is not valid