NATS: remove variadic argument for the connection string

[mdelapenya]

          I like this PR because it's pointing to bad designs on our side. E.g. this function should not receive the variadic argument at all, or we could check here if the NATS query string supports parameters that could be appended, demonstrating we have a bug here.

Originally posted by @mdelapenya in #2949 (comment)

[jasonyunicorn]

@mdelapenya I read through the NATS Docs on connecting and did not see any reference or mention of query parameter support, so the variadic argument is not needed at all.

LMK if you want a PR for it, it's a 2-liner.

[mdelapenya]

@jasonyunicorn yes please.

Mark it as a breaking change as the signature of the method will change 🙏