False errors when allOf is in request schema

[renom]

https://github.com/wallarm/api-firewall/blob/main/internal/platform/validator/unknown_parameters_request.go#L90-L129

It seems findUnknownParamsInJSONBody doesn't handle allOf properly.

requestBody:
  required: true
  content:
    application/json:
      schema:
        allOf:
          - $ref: "#/components/schemas/Schema1"
          - $ref: "#/components/schemas/Schema2"

Returns body parameter not defined in the OpenAPI specification for parameters that's actually defined in one of the schemas.