feat: Support new version of Pydantic by fixing deprecation

[Some7hing0riginal]

Describe the feature

Support new version of Pydantic to remove deprecated call:

.venv/lib/python3.12/site-packages/spectree/plugins/falcon_plugin.py:184: PydanticDeprecatedSince20: The `parse_obj` method is deprecated; use `model_validate` instead. Deprecated in Pydantic V2.0 to be removed in V3.0. See Pydantic V2 Migration Guide at https://errors.pydantic.dev/2.10/migration/
    req.context.json = json.parse_obj(media)

Additional context

No response

[kemingy]

• v1/v2 download percentage

Since there are still lots of people using pydantic v1 (may not 100% accurate for spectree but I don't have other telemetries), I still plan to make it compatible for pydantic v1&v2. Until they release v3, which will drop all the v1 legacy interfaces.

• related to Migrate deprecated Pydantic function #395