Error handling with dynamic clients

When executing GraphQL operations using a dynamic client, the application receives back an instance of io.smallrye.graphql.client.Response that encapsulates the whole response from the service, including potential errors. Errors are represented as io.smallrye.graphql.client.GraphQLError and can be inspected after retrieving a list of all errors using response.getErrors().

It is also possible to convert a response's errors into a io.smallrye.graphql.client.GraphQLClientException by calling throwExceptionIfErrors() - the response has to be cast to ResponseImpl for this as of now. This method will, if there are any errors in the response, convert the errors into a GraphQLClientException and throw it.