fix: FluentAutocomplete should throw on use of SelectedOption

[davhdavh]

🐛 Bug Report

FluentAutocomplete throws if setting Multiple to false, but if set/bind the SelectedOption it just doesn't work.

💻 Repro or Code Sample

NA

🤔 Expected Behavior

Throw like Multiple

😯 Current Behavior

Silently does not work

💁 Possible Solution

Alternative to throw would be to set MaximumSelectedOptions to null/1 and fix the code to use it SelectedOption when MaximumSelectedOptions is null/1 to make it consistent with other list components.