According to Quora, spacesuits are designed in such a way that astronauts are incapable of smelling their own farts while wearing one. The noise of the fart is muffled by a diaper, and the helmet section is sealed from the rest of the body, preventing gas exchange between your butt and your nose. A far more common problem is what happens when an astronaut farts
without wearing a spacesuit, such as
farting inside a pressurized cabin on a space station. But that's a different question, so I won't get into it.
To answer OP's question: yes, but it depends. Do you think non-smelly farts are funny?
Personally, I don't even notice farts if they don't smell. The only time I think a fart of mine is really really funny is when it smells so bad my eyes water. So theoretically speaking, "If you were in a space suit and farted and it smelled really bad like so bad your eyes started watering would you think it was really really funny?" would be a yes, as the funniness of farts is contingent upon their smell, and an eye-watering fart is inherently funny. However, practically speaking, it won't go down that way; you might fart, and the fart might smell so bad your eyes
would water, but you'll never know because you'll never smell it. Thus, if I farted while wearing a space suit, I would be unlikely to laugh, as for all I'd know it was just a boring, routine fart.