Issue with cloudevents dependency #403

Hi,

There was a change in this dependency that happened with 3597a56, changing the versions in the pyproject.toml file from this:

cloudevents>=1.2.0,<=1.11.0

To this:

cloudevents>=1.12.0,<=1.12.0

I am no don't think this change makes sense. This should either be reverted back to the looser requirements, or be made ==1.12.0.

Regards,
Sarthak