Represent build tag as `u64` (#4253)
## Summary
The build tags in this case are like, e.g., `202206090410`. That's
larger than a `u32`, so we're rejecting the wheel. In theory build tags
could be even larger, but we already use `u64` for version segment so I
think it's fine to keep that constraint here.
I'm going to look into surfacing these errors separately.
Closes https://github.com/astral-sh/uv/issues/4252.
## Test Plan
`cargo run pip install monailabel`
