Get Account Public Key
Get the public key associated with an account ID.
Request:
- requestType is getAccountPublicKey
 - account is the account ID
 - requireBlock is the block ID of a block that must be present in the blockchain during execution (optional)
 - requireLastBlock is the block ID of a block that must be last in the blockchain during execution (optional)
 
Response:
- publicKey (S) is the 32-byte public key associated with the account, returned as a hex string
 - lastBlock (S) is the last block ID on the blockchain (applies if requireBlock is provided but not requireLastBlock)
 - requestProcessingTime (N) is the API request processing time (in millisec)