Constant catalyst_toolbox::rewards::proposers::INVALID_CHAIN_ID_UTF8_MSG

const INVALID_CHAIN_ID_UTF8_MSG: &str = "chain_proposal_id's serde impls encode strings as `Vec<u8>`, panicking if non-UTF-8 is detected, so it should be safe to assume `chain_proposal_id` contains valid UTF-8 (probably a base16 string)";