GraphQL Services Allow the Use of Empty Record Types as GraphQL Object Types

[DimuthuMadushan]

Description:
The following GraphQL service should return a compilation error. Currently it's compiling successfully.

import ballerina/graphql;

type Project record {
};

service /projects on new graphql:Listener(8080) {
    resource function get project() returns Project {
        return {};
    }
}