§ 5-311. Certain agreements between husband and wife void. Except as provided in § 236 of the domestic relations law, a husband and wife cannot contract to alter or dissolve the marriage or to relieve either of his or her liability to support the other in such a manner that he or she will become incapable of self-support and therefore is likely to become a public charge. An agreement, heretofore or hereafter made between a husband and wife, shall not be considered a contract to alter or dissolve the marriage unless it contains an express provision requiring the dissolution of the marriage or provides for the procurement of grounds of divorce.