After a quick Google search I learned that the answer is "kinda".

Just like us they do produces gases as part of their metabolism. That gas has to go somewhere. Some of it is absorbed into their hemolyph (blood) and expelled into the air through openings in their exoskeleton. But it's very unlikely that none of that gas exits through their anus.

Also, people have spotted "bubbles" on insects trapped in amber right where their anus is, it's likely that those are encased fart-bubbles.