Add dynamic password support

[vitaly-t]

As per PR #1926, to allow dynamic passwords.

[vitaly-t]

Released in v9.0.2.

This is strictly a TypeScript-side update, to let you for the password pass in not only a string, but also a function that returns the password, which can even be asynchronous.

const cn = {
    database: 'my-db',
    password: () => 'pass123'
}