Fix GraphQL tests for latest Spring GraphQL

Author: artembilan

spring-integration-graphql/src/test/java/org/springframework/integration/graphql/outbound/GraphQlMessageHandlerTests.java

@@ -316,7 +316,7 @@ ExecutionGraphQlService graphQlService(GraphQlSource graphQlSource) {
 
 		@Bean
 		GraphQlSource graphQlSource(AnnotatedControllerConfigurer annotatedDataFetcherConfigurer) {
-			return GraphQlSource.builder()
+			return GraphQlSource.schemaResourceBuilder()
 					.schemaResources(new ClassPathResource("graphql/test-schema.graphqls"))
 					.configureRuntimeWiring(annotatedDataFetcherConfigurer)
 					.build();