In a similar format to the previous answer, here's an updated count of spells with saving throws from all official published sources available on D&D Beyond. It’s current as of 14/01/2022.
I am aware of one spell, Nathair's mischief from Fizban’s Treasury of Dragons, which doesn’t list a primary save, but can force either a Wisdom or Dexterity saving throw, depending on the random effect rolled. I have counted it as both, which is why the total spell count here seems slightly lower than it ought to be. It’s possible there are other such spells but there is no easy way to search for them; I believe this list is still pretty indicative of the frequency of saving throws in spells.
I note a significant jump in the number of spells with Constitution saves, but only three recently published spells have them, so this may indicate a previous counting error on my part.
For a list of official sources for spells, and how to find them on D&D Beyond, see this question: What official books contain spells?