Modify return on post /loggers to HTTP 204

This commit alter the return http status code from 200 to 204.

Closes gh-8919

spring-boot-actuator-docs/src/restdoc/java/org/springframework/boot/actuate/hypermedia/EndpointDocumentation.java

@@ -126,7 +126,7 @@ public class EndpointDocumentation {
 				.perform(post("/application/loggers/org.springframework.boot")
 						.contentType(ActuatorMediaTypes.APPLICATION_ACTUATOR_V2_JSON)
 						.content("{\"configuredLevel\": \"DEBUG\"}"))
-				.andExpect(status().isOk()).andDo(document("set-logger"));
+				.andExpect(status().isNoContent()).andDo(document("set-logger"));
 	}
 
 	@Test

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/LoggersMvcEndpoint.java

@@ -71,7 +71,7 @@ public class LoggersMvcEndpoint extends EndpointMvcAdapter {
 		try {
 			LogLevel logLevel = getLogLevel(configuration);
 			this.delegate.setLogLevel(name, logLevel);
-			return ResponseEntity.ok().build();
+			return ResponseEntity.noContent().build();
 		}
 		catch (IllegalArgumentException ex) {
 			return ResponseEntity.badRequest().build();

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/LoggersMvcEndpointTests.java

@@ -150,7 +150,7 @@ public class LoggersMvcEndpointTests {
 	@Test
 	public void setLoggerUsingApplicationJsonShouldSetLogLevel() throws Exception {
 		this.mvc.perform(post(PATH + "/ROOT").contentType(MediaType.APPLICATION_JSON)
-				.content("{\"configuredLevel\":\"debug\"}")).andExpect(status().isOk());
+				.content("{\"configuredLevel\":\"debug\"}")).andExpect(status().isNoContent());
 		verify(this.loggingSystem).setLogLevel("ROOT", LogLevel.DEBUG);
 	}
 
@@ -158,7 +158,7 @@ public class LoggersMvcEndpointTests {
 	public void setLoggerUsingActuatorV2JsonShouldSetLogLevel() throws Exception {
 		this.mvc.perform(post(PATH + "/ROOT")
 				.contentType(ActuatorMediaTypes.APPLICATION_ACTUATOR_V2_JSON)
-				.content("{\"configuredLevel\":\"debug\"}")).andExpect(status().isOk());
+				.content("{\"configuredLevel\":\"debug\"}")).andExpect(status().isNoContent());
 		verify(this.loggingSystem).setLogLevel("ROOT", LogLevel.DEBUG);
 	}