Default http.Client and http.Transport can be really slow. Also on
windows Timeout: time.Second was not enough. Probably network related
issue. As mentioned in https://github
.com/nspcc-dev/neo-go/issues/2975#issuecomment-1750523651 forcely use
only tcp4 and FallbackDelay: -1. This made TestRPC little bit faster so
gh windows runner can manage it without timeout or POST request fails.
Close#2975Close#3314
Signed-off-by: Ekaterina Pavlova <ekt@morphbits.io>