data of the GraphQL execution result.DataFetchers.DataFetcherExceptionResolver that pre-implements the
asynchronous contract and exposes the following synchronous methods:
DataFetcherExceptionResolverAdapter.resolveToSingleError(java.lang.Throwable, graphql.schema.DataFetchingEnvironment)
DataFetcherExceptionResolverAdapter.resolveToMultipleErrors(java.lang.Throwable, graphql.schema.DataFetchingEnvironment)
DataFetchingEnvironment or GraphQLContext arguments.null which
we cannot use in annotation attributes.WebGraphQlTester.Builder.defaultHeader(String, String...) that provides
access to the underlying headers to inspect or modify directly.