Removed use of ssl_required in test
Removed use of ssl_required in test

Some tests did still reference ssl_required (which has been
removed, tls_required is the proper field name). This has no
impact since in these tests, the value was set to false.

Signed-off-by: Ivan Kozlovic <a15f8b81a160b4eebe5c84e9e3b65c87b9b2f18e@synadia.com>

apcera/nats,nats-io/go-nats,wallyqs/go-nats,wallyqs/go-nats,apcera/nats,nats-io/go-nats,nats-io/nats,nats-io/nats