When running `script/bundle` with the new `-2` flag, we needed to adjust
the fat-binary creation step to look for the binary called `Zed2`.
We also fixed a source of intermittent build failures in `script/bundle`
due to running multiple `swift build` processes concurrently for the
`live_kit_client2` crate, building for the two architectures.
Release Notes:
NA
Max Brunsfeld
4f4ef4a357