Deprecate falcon.testing.httpnow()

[vytas7]

Apparently this ancient alias has survived unnoticed from the very early iterations of the framework.

Wrap it in the @deprecated(...) decorator so that we don't miss it again.

Write that it will be removed in Falcon 5.0 in the deprecation message.

[kyash99252]

Hello @vytas7 ! I’d love to work on this issue as a first-time contributor. Is that okay?

[CaselIT]

Sure! If you have any question feel free to ask it here!

[arthurprioli]

Hey guys, I know I'm not the contributor in this issue but I have a suggestion for y'all.
To solve this, do we just have to add in init on testing?

httpnow = deprecated('This method is deprecated and will be removed in Falcon 5.0.')( _util.http_now )

[vytas7]

Hi @arthurprioli, yes, but we also need to add a test asserting that a deprecation warning is emitted upon referencing this method.

We also need to check with @kyash99252, maybe there is a PR already on the way?