92.21 Certificate as to sanitary condition of buildings.—Every owner, agent, or lessee of any building or buildings used for the purpose of providing board and lodgings for the entertainment of guests, containing 10 rooms or more, who shall have obtained and posted a certificate as provided by law, may present the same as evidence in the owner’s, agent’s, or lessee’s defense in any suit in any of the courts in this state in which damages are claimed for injuries from alleged unsanitary conditions of said buildings and premises.