Do not set ConversionService on AnnotatedControllerConfigurer

After 0b449d89e1,
the ConversionService on AnnotatedControllerConfigurer is an internally
managed instance that is customized with FormatterRegistrar rather than
set.

Closes gh-29636

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/graphql/GraphQlAutoConfiguration.java

@@ -39,7 +39,6 @@ import org.springframework.boot.context.properties.EnableConfigurationProperties
 import org.springframework.context.annotation.Bean;
 import org.springframework.core.io.Resource;
 import org.springframework.core.io.support.ResourcePatternResolver;
-import org.springframework.format.support.DefaultFormattingConversionService;
 import org.springframework.graphql.GraphQlService;
 import org.springframework.graphql.data.method.annotation.support.AnnotatedControllerConfigurer;
 import org.springframework.graphql.execution.BatchLoaderRegistry;
@@ -130,9 +129,7 @@ public class GraphQlAutoConfiguration {
 	@Bean
 	@ConditionalOnMissingBean
 	public AnnotatedControllerConfigurer annotatedControllerConfigurer() {
-		AnnotatedControllerConfigurer annotatedControllerConfigurer = new AnnotatedControllerConfigurer();
-		annotatedControllerConfigurer.setConversionService(new DefaultFormattingConversionService());
-		return annotatedControllerConfigurer;
+		return new AnnotatedControllerConfigurer();
 	}
 
 	private <T> List<T> toList(ObjectProvider<T> provider) {