function checkUnsupportedRoutes(reqMethod, reqQuery, reqHeaders) {
    const method = routeMap[reqMethod];
    if (!method || (!reqQuery && !reqHeaders)) {
        return { error: errors.MethodNotAllowed };
    }
    return { method };
}
Ensure only supported methods are supported, otherwise, return an error
@param {string} reqMethod - the HTTP verb of the request
@param {string} reqQuery - request query
@param {object} reqHeaders - request headers
@returns {object} - method or error