chore: remove unused sync_wrapper

[tottoto]

sync_wrapper crate seems not to be used.

[seanmonstar]

Oh it's not used? It probably should be, so that reqwest::Body can allow !Sync streams.

[paolobarbolini]

I've tried reintroducing it doesn't look possible because of the functions taking shared references https://github.com/paolobarbolini/reqwest/tree/unsync-body

[musicinmybrain]

If you do end up reintroducing it, please update the dependency to 1.0.0 or later. This doesn’t involve any incompatible changes: the only change from 0.1.2 to 1.0.0 was replacing ’ with ' in the description in Cargo.toml.