Inherit show-details property in health groups

Update `Group` properties so that the `showDetails` value does not
inherit `Show.NEVER`. Prior to this commit, the `Group` properties
would not correctly inherit a `showDetails` value from the main
`management.endpoint.health.show-details` property.

See gh-22022

Author: polarbear567

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/health/HealthEndpointProperties.java

@@ -27,6 +27,7 @@
  * Configuration properties for {@link HealthEndpoint}.
  *
  * @author Phillip Webb
+ * @author Leo Li
  * @since 2.0.0
  */
 @ConfigurationProperties("management.endpoint.health")
@@ -56,6 +57,11 @@ public static class Group extends HealthProperties {
 		 */
 		private Set<String> exclude;
 
+		/**
+		 * The default value of this field should be null for group.
+		 */
+		private Show showDetails;
+
 		public Set<String> getInclude() {
 			return this.include;
 		}
@@ -72,6 +78,16 @@ public void setExclude(Set<String> exclude) {
 			this.exclude = exclude;
 		}
 
+		@Override
+		public Show getShowDetails() {
+			return this.showDetails;
+		}
+
+		@Override
+		public void setShowDetails(Show showDetails) {
+			this.showDetails = showDetails;
+		}
+
 	}
 
 }

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/health/AutoConfiguredHealthEndpointGroupsTests.java

@@ -43,6 +43,7 @@
  * Tests for {@link AutoConfiguredHealthEndpointGroups}.
  *
  * @author Phillip Webb
+ * @author Leo Li
  */
 class AutoConfiguredHealthEndpointGroupsTests {
 
@@ -308,6 +309,16 @@ void createWhenHasGroupSpecificHttpCodeStatusMapperPropertyAndGroupQualifiedBean
 				});
 	}
 
+	@Test
+	void createWhenNoDefinedGroupsShowDetails() {
+		this.contextRunner.withPropertyValues("management.endpoint.health.show-details=always",
+				"management.endpoint.health.group.a.include=*").run((context) -> {
+					HealthEndpointGroups groups = context.getBean(HealthEndpointGroups.class);
+					HealthEndpointGroup groupA = groups.get("a");
+					assertThat(groupA.showDetails(SecurityContext.NONE)).isTrue();
+				});
+	}
+
 	@Configuration(proxyBeanMethods = false)
 	@EnableConfigurationProperties(HealthEndpointProperties.class)
 	static class AutoConfiguredHealthEndpointGroupsTestConfiguration {