feature: OAS3 object parameter support (#4563)

* render suitable interface for `type: object` parameters

* validate OAS3 object parameters correctly

* display parameter validation errors

* remove irrelevant css classes

* rm comment

* fix failing tests

* add validateParam tests

* add enzyme tests for object parameter rendering

* run actual tests first

src/style/_form.scss

@@ -51,7 +51,8 @@ input[type=text],
 input[type=password],
 input[type=search],
 input[type=email],
-input[type=file]
+input[type=file],
+textarea
 {
     min-width: 100px;
     margin: 5px 0;