Stabilize the situation around WebSocketRequest and its usage

[redlickigrzegorz]

Maybe we can create a similar Event class to the one we have for REST? It should simplify the work with it 😉

Originally posted by @redlickigrzegorz in #102 (comment)

It would be nice to confirm the documentation that you used as I see that all these keys are under context 🤷

Originally posted by @redlickigrzegorz in #102 (comment)

I started thinking whether these two classes are really that similar to inherit from the same base one 🤔

Originally posted by @redlickigrzegorz in #102 (comment)

This line should be removed after the changes you made.

Originally posted by @redlickigrzegorz in #102 (comment)

It looks like we should allow passing body=None instead of ignoring the error.

Originally posted by @redlickigrzegorz in #102 (comment)

def test__json_body__raises_error_when_json_is_malformed(self) -> None:

Originally posted by @redlickigrzegorz in #102 (comment)