chore(turbopack): Bump rustc-hash from 2.1.0 to 2.1.1 (#78721)
This includes https://github.com/rust-lang/rustc-hash/pull/56
Apparently 2.1.0 has a bug that can cause lots of hashtable collisions for very large maps with more than `2^20` elements. We have some very large maps, so this seems potentially concerning.
