All the places in code that configure the mentioned creds builder
from client_|server_encryption_options now do it the same way.
This patch generalizes it all in the utils:: helper.
The alternator code "ignores" require_client_auth and truststore
keys, but it's easy to make the generalized helper be compatible.
Also make the new helper coroutinized from the beginning.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
e02b39ca3d