Bitswap: Expose peer-pruning option

There is a parameter [here](https://github.com/ipfs/boxo/blob/364c5040ec91ec8e2a61446e9921e9225704c34d/bitswap/client/internal/session/sessionwantsender.go#L16).

Any peer that responds with 16 dont-haves is pruned (availability turned off). We might expose it as an option as it seems relatively relevant wrt to bitswap traffic control.