Fix SASL to bubble up errors, enable SASL tests in CI, and add informative empty SASL password message

[sehrope]

Couple of SASL related commits here:

1. Enables SASL testing in GitHub actions CI.
2. Adds a basic unit test for SASL password being a string.
3. Catches SASL handling errors and bubbles them up as error events.
4. Adds an explicit check to the SASL handling for an empty password so the user gets an informative email.

Number 3 should actually close out #2757. Interestingly this was brought up in 2019 when the SASL code was first added: #1927. This should close that out too.

[brianc]

aww thank you, this is an awesome change! 💃 Will get this merged & pushed out ASAP!

[verycosy]

AWESOME! Thank you for your commits