Improve debug logging of requests to actuator endpoints on WebFlux

See gh-30880

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/web/reactive/AbstractWebFluxEndpointHandlerMapping.java

@@ -384,6 +384,11 @@ public abstract class AbstractWebFluxEndpointHandlerMapping extends RequestMappi
 			return this.operation.handle(exchange, body);
 		}
 
+		@Override
+		public String toString() {
+			return this.operation.toString();
+		}
+
 	}
 
 	/**
@@ -402,6 +407,11 @@ public abstract class AbstractWebFluxEndpointHandlerMapping extends RequestMappi
 			return this.operation.handle(exchange, null);
 		}
 
+		@Override
+		public String toString() {
+			return this.operation.toString();
+		}
+
 	}
 
 	private static class WebFluxEndpointHandlerMethod extends HandlerMethod {