Fix GH-12296: Ignore pwd empty check

[SakiTakamachi]

fixes #12296

This is a minimal fix. It now works even if we specify an empty string for the password.
Other modifications will be made to master.

[SakiTakamachi]

@NattyNarwhal
Could you check it out?

[NattyNarwhal]

What if null is passed as password? I forgot how spprintf handles that; if it doesn't like it, then an empty string would work. Just means you have to set password to an empty string if it's null. (edit: Or just do a null check and require an empty string be passed.)

I also don't know if it makes sense to do the same to UID.

[SakiTakamachi]

Since the argument is expecting a string, I don't think null will be passed here. (Except for bugs, of course)

I think either of the empty string checks for uid is fine. There's not that much difference between the two tbh.

[SakiTakamachi]

Maybe I should close this one. If I merge this, connections that should not specify a password will never be able to connect.