Allow configprops endpoint stringify primitive wrappers

Update `ConfigurationPropertiesReportEndpoint` so that primitive
wrapper input values in the Environment are stringified for display.

Fixes gh-36076

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/context/properties/ConfigurationPropertiesReportEndpoint.java

@@ -394,7 +394,7 @@ public class ConfigurationPropertiesReportEndpoint implements ApplicationContext
 	}
 
 	private Object stringifyIfNecessary(Object value) {
-		if (value == null || value.getClass().isPrimitive()) {
+		if (value == null || ClassUtils.isPrimitiveOrWrapper(value.getClass()) || value instanceof String) {
 			return value;
 		}
 		if (CharSequence.class.isAssignableFrom(value.getClass())) {