model validate can't get all parameters from operation in function validateRequest

[ankhyk]

In function validateRequest, model validate can only get parameters under request methods, public parameters will be missed

For example:

"paths": {
  "(path)": {
    "parameters": [A, B, C]
    "put": {
      "parameters": [D]
    }
  }
}

In this example, function validateRequest can only validate parameter-D then will report error OBJECT_MISSING_REQUIRED_PROPERTY for parameter-A, parameter-B and parameter-C