Reference count QUIC_TOKENS

Reference count QUIC_TOKENS

closer reading of RFC 9000 indicates that a NEW_TOKEN token can be
(re)used repeatedly.

so instead of creating a use once and discard pattern in the token api.
Let the tokens stick around until they are replaced with a new token
from the server.  To do this, we need to ref count the tokens so that we
don't accidentally free them while a given client is waiting to send an
initial frame making use of them.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Saša Nedvědický <sashan@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/26517)