`rustls/ring` is always active with `http_wait` feature

[skeggse]

For FIPS-compliant workspaces, it's important to omit unverified cryptographic implementations like ring. This is possible by restricting the enabled features for testcontainers and pulling in #847.

The http_wait feature pulls in reqwest with extra features not inherently important for the http_wait functionality. In particular, it pulls in the rustls-tls and rustls-tls-native-roots features, which transitively depend on ring. Since TLS isn't a necessary requirement for testing containers, it'd be nice if we could exclude these features from the optional reqwest dependency.

Does that seem feasible? I'm not sure what sort of change that would be for this crate.