Skipping null values from rendering

[sadikoff]

Hi there!

This should fix a weird situation when we are rendering stringified null value attribute and stimulus using null string as a value instead of just skipping it.

[weaverryan]

Thanks for this @sadikoff!

To be fully clear, if you passed a true null to stimulus_controller() for a value that is a String type in your Stimulus controller, then:

Before this change: The value would be the string null (literally those 4 charaters) in JavaScript.
After this change: The value will be '' empty quotes. It still won't be a true null in your controller, but that's just because Stimulus expects the type to be a String always, so it gives you a astring.