[coinbase-pro] HttpStatusIOException (HTTP code 408) in background processing

[badgerwithagun]

Happens fairly regularly. Looks closely related to SocketTimeoutException and some of the gateway errors, both of which we already treat as transient and effectively ignore.

However, all these together suggest that maybe we're getting connections closed prematurely which means maybe we're not acting fast enough.

Either make this ignored (in which case it should really be converted by XChange into a recognised exception) or fix it.