Fixes compilation errors and polishing

Author: spencergibb

spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/config/ContextFunctionCatalogInitializer.java

@@ -127,7 +127,7 @@ protected void register(BeanDefinitionRegistry registry, ConfigurableListableBea
 					.containsBeanDefinition(AnnotationConfigUtils.CONFIGURATION_ANNOTATION_PROCESSOR_BEAN_NAME)) {
 				// Switch off the ConfigurationClassPostProcessor
 				this.context.registerBean(AnnotationConfigUtils.CONFIGURATION_ANNOTATION_PROCESSOR_BEAN_NAME,
-						DummyProcessor.class, () -> new DummyProcessor());
+						DummyProcessor.class, DummyProcessor::new);
 				// But switch on other annotation processing
 				AnnotationConfigUtils.registerAnnotationConfigProcessors(this.context);
 			}
@@ -137,7 +137,7 @@ protected void register(BeanDefinitionRegistry registry, ConfigurableListableBea
 
 			if (ClassUtils.isPresent("com.google.gson.Gson", null) && "gson".equals(preferredMapper)) {
 				if (this.context.getBeanFactory().getBeanNamesForType(Gson.class, false, false).length == 0) {
-					this.context.registerBean(Gson.class, () -> new Gson());
+					this.context.registerBean(Gson.class, Gson::new);
 				}
 				this.context.registerBean(JsonMapper.class, () -> new ContextFunctionCatalogAutoConfiguration.JsonMapperConfiguration().jsonMapper(this.context));
 			}
@@ -183,7 +183,7 @@ && new ClassPathResource(basePackage.replace(".", "/")).exists()) {
 					ConversionService conversionService = new DefaultConversionService();
 					return new SimpleFunctionRegistry(conversionService, messageConverter, this.context.getBean(JsonMapper.class));
 				});
-				this.context.registerBean(FunctionProperties.class, () -> new FunctionProperties());
+				this.context.registerBean(FunctionProperties.class, FunctionProperties::new);
 				this.context.registerBean(FunctionRegistrationPostProcessor.class,
 						() -> new FunctionRegistrationPostProcessor(this.context.getAutowireCapableBeanFactory()
 								.getBeanProvider(FunctionRegistration.class)));
@@ -199,7 +199,7 @@ private void performPreinitialization() {
 
 					@Override
 					public void run() {
-						runSafely(() -> new DefaultFormattingConversionService());
+						runSafely(DefaultFormattingConversionService::new);
 					}
 
 					public void runSafely(Runnable runnable) {