Any employer who discharges, or in any other manner discriminates against any employee because such employee has testified or is about to testify, or because such employer believes that said employee may testify in any investigation or proceedings relative to the enforcement of RCW 49.12.010 through 49.12.180, shall be deemed guilty of a misdemeanor and upon conviction thereof, shall be punished by a fine of from twenty-five dollars to one hundred dollars for each such misdemeanor.