1.12.0-rc18

(fix): Make the behavior between a wrapped request with body properties and normal body request consistent. Previously, a wrapped request with body properties would not omit null values even if the JSON configuration is configured to omit null values.

(fix): Fix a bug where required properties that were [JsonIgnore] threw an error during serialization.

(feat): Improve performance of query string value to string conversion by relying less on JsonSerializer and more on ToString().