Not a film, but a novel:
Starflight 3000 by R.W. Mackelworth
If I remember, it was about this asteroid called "The Biosphere" that got hollowed out and sent on relativistic speeds through deep space to seed other solar systems with human colonies. The inside of it was set up like a giant rural town with massive skies, and a foot print the size of New York. And that's a cool ass premise.
But the book was so fucking milquetoast and bland. I could not tell you anything about the protagonist, their challenges, or anything.