revertrisk: add pydantic validation

[isaranto]

• add validation in the parent model
• add validation in revertrisk
• define the LiftWing class request function (the parent function) and let
  child classes just call super() with the appropriate validation class in the decorator

An example of making a request where the parameter lang is missing:

Traceback (most recent call last):
  File "/Users/isaranto/repoz/liftwing-python/test.py", line 8, in <module>
    print(client.request(payload={"rev_id": 123456}))
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/isaranto/repoz/liftwing-python/liftwing/utils/validator.py", line 13, in wrapper
    _ = model(**payload)
        ^^^^^^^^^^^^^^^^
  File "/Users/isaranto/repoz/liftwing-python/.venv/lib/python3.11/site-packages/pydantic/main.py", line 176, in __init__
    self.__pydantic_validator__.validate_python(data, self_instance=self)
pydantic_core._pydantic_core.ValidationError: 1 validation error for RevertRiskPayload
  Value error, 'lang' parameter is required in the payload. [type=value_error, input_value={'rev_id': 123456}, input_type=dict]
    For further information visit https://errors.pydantic.dev/2.7/v/value_error

Bug: T366015

[AikoChou]

Hi Ilias, thank you for working on this. I don't have much experience on pydantic, so not sure about the best practices here. But I checked their documentation and have some suggestions. :)

[AikoChou]

LGTM :)

[AikoChou]

I like this solution 😃