FEAT: use None queue name in event() decorator function() (uses func.__name__ if it's None)

[kolkre]

Description

Adds a possibility to use None queue name in event() decorator function

Type of change

• New feature (non-breaking change which adds functionality)

Checklist

• My code follows the style guidelines of this project (scripts/lint.sh has no errors)
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[Lancetnik]

@spectacularfailure sorry, I am not stop you earlier. This feature was implemented in the first project drafts, but than I removed it.
I suppose, this case is conflict with the Explicit is better than implicit principle from the PEP-20, thus I don't like an idea to add any magic to the project logic.