No exception when the contract contains operation request/response with unsupported media type.

[dprincethg]

I've tried to create a contract from an OpenAPI file containing some operations with "application/json" request/response body media type, and others operations with other types (multipart/form-data,...)

But the creation fails as only "application/json" is supported.
io.vertx.openapi.contract.OpenAPIContractException: The passed OpenAPI contract contains a feature that is not supported: Operation getLocationsAsFile defines a response with an unsupported media type. Supported: application/json

I would prefer to allow the contract creation, and raise exceptiuon only during validation.

Because I use the contract only to validate "application/json" operations with "Vert.x OpenAPI Router".