Refine ConfigurationClassPostProcessor behavior in native images

This commit refines ConfigurationClassPostProcessor behavior in
native images by skipping configuration classes enhancement
instead of raising an error.

See spring-projects-experimental/spring-graalvm-native#248 for
more details.

Closes gh-26236

spring-context/src/main/java/org/springframework/context/annotation/ConfigurationClassPostProcessor.java

@@ -427,15 +427,11 @@ public class ConfigurationClassPostProcessor implements BeanDefinitionRegistryPo
 				configBeanDefs.put(beanName, (AbstractBeanDefinition) beanDef);
 			}
 		}
-		if (configBeanDefs.isEmpty()) {
+		if (configBeanDefs.isEmpty() || IN_NATIVE_IMAGE) {
 			// nothing to enhance -> return immediately
 			enhanceConfigClasses.end();
 			return;
 		}
-		if (IN_NATIVE_IMAGE) {
-			throw new BeanDefinitionStoreException("@Configuration classes need to be marked as " +
-					"proxyBeanMethods=false. Found: " + configBeanDefs.keySet());
-		}
 
 		ConfigurationClassEnhancer enhancer = new ConfigurationClassEnhancer();
 		for (Map.Entry<String, AbstractBeanDefinition> entry : configBeanDefs.entrySet()) {