Is it a problem to leave a sprinkler line through concrete shed footing?
People put flexible pipes inside concrete all the time (this is how heated floors are made)

you should space it away from the floor and trench mesh so that it does not become a conduit for moisture (from the soil) and oxygen to attack the reinforcing steel

If you have more of that line and some elbows now would be a good time to move it. But if you're feeling lazy it doesn't look particularly hard to replace the under-slab section with an external loop at a later date. if needed.