Anti Amplification does not apply to Clients

[WesleyRosenblum]

8.1. Address Validation during Connection Establishment

In addition to sending limits imposed prior to address validation, servers are also constrained in what they can send by the limits set by the congestion controller. Clients are only constrained by the congestion controller.

New paths are currently started in the AmplificationLimited state, even for the client: https://github.com/awslabs/s2n-quic/blob/a172ff319c1fd1b507fb5e3a41def0e1434e7897/quic/s2n-quic-transport/src/path/mod.rs#L114-L117