Observed behavior
When Drain is called on a NATS connection object and it is nil, the program panics; while calling Drain on a Subscription does not lead to a panic and returns error.
Expected behavior
I expect that calling Drain() on a NATS connection, an error be returned, instead of panic.
Server and client version
v1.32.0
Host environment
No response
Steps to reproduce
Create a NATS connection with an invalid URL, and the call Drain() on it.