Article 1, Section 10, Paragraph 3 states:
No State shall, without the Consent of Congress, lay any Duty of Tonnage, keep Troops, or Ships of War in time of Peace, enter into any Agreement or Compact with another State, or with a foreign power, or engage in War, unless actually invaded, or in such imminent Danger as will not admit of delay.
Not as of Virginia v Tennessee in 1893. Congressional approval is only required for pacts if the states involved increase their power above the federal government's.
From what I've read up on it. Cuomo's pact is valid unless they keep their states closed if Trump says open or vice versa.