Make LogCorrelationPropertySource an EnumerablePropertySource

Change `LogCorrelationPropertySource` to an `EnumerablePropertySource`
to reduce the likelihood of `Binder` errors.

Closes gh-38349

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/tracing/LogCorrelationEnvironmentPostProcessor.java

@@ -20,6 +20,7 @@ import org.springframework.boot.SpringApplication;
 import org.springframework.boot.env.EnvironmentPostProcessor;
 import org.springframework.boot.logging.LoggingSystem;
 import org.springframework.core.env.ConfigurableEnvironment;
+import org.springframework.core.env.EnumerablePropertySource;
 import org.springframework.core.env.Environment;
 import org.springframework.core.env.PropertySource;
 import org.springframework.util.ClassUtils;
@@ -45,7 +46,7 @@ class LogCorrelationEnvironmentPostProcessor implements EnvironmentPostProcessor
 	/**
 	 * Log correlation {@link PropertySource}.
 	 */
-	private static class LogCorrelationPropertySource extends PropertySource<Object> {
+	private static class LogCorrelationPropertySource extends EnumerablePropertySource<Object> {
 
 		private static final String NAME = "logCorrelation";
 
@@ -56,6 +57,11 @@ class LogCorrelationEnvironmentPostProcessor implements EnvironmentPostProcessor
 			this.environment = environment;
 		}
 
+		@Override
+		public String[] getPropertyNames() {
+			return new String[] { LoggingSystem.EXPECT_CORRELATION_ID_PROPERTY };
+		}
+
 		@Override
 		public Object getProperty(String name) {
 			if (name.equals(LoggingSystem.EXPECT_CORRELATION_ID_PROPERTY)) {

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/tracing/LogCorrelationEnvironmentPostProcessorTests.java

@@ -23,6 +23,8 @@ import org.springframework.boot.logging.LoggingSystem;
 import org.springframework.boot.test.util.TestPropertyValues;
 import org.springframework.boot.testsupport.classpath.ClassPathExclusions;
 import org.springframework.core.env.ConfigurableEnvironment;
+import org.springframework.core.env.EnumerablePropertySource;
+import org.springframework.core.env.PropertySource;
 import org.springframework.core.env.StandardEnvironment;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -64,4 +66,13 @@ class LogCorrelationEnvironmentPostProcessorTests {
 			.isFalse();
 	}
 
+	@Test
+	void postProcessEnvironmentAddsEnumerablePropertySource() {
+		this.postProcessor.postProcessEnvironment(this.environment, this.application);
+		PropertySource<?> propertySource = this.environment.getPropertySources().get("logCorrelation");
+		assertThat(propertySource).isInstanceOf(EnumerablePropertySource.class);
+		assertThat(((EnumerablePropertySource<?>) propertySource).getPropertyNames())
+			.containsExactly(LoggingSystem.EXPECT_CORRELATION_ID_PROPERTY);
+	}
+
 }