In any suit, action, or proceeding involving the validity or enforcement of or relating to any contract of the hospital or health center commission, such commission shall be conclusively deemed to have become created as a body politic and corporate, and to have become established and authorized to transact business and exercise its powers, upon proof of the adoption of a resolution by the governing body of each locality for which the commission is created declaring the need for such commission, and, if more than one political subdivision is involved, that it unites with the other political subdivisions in declaring such needs. A copy of the resolution, certified by the clerk of the locality by which it is adopted, shall be admissible in evidence in any suit, action or proceeding.