Polishing.

Clean up residual observations after tests.

See #5082
Original pull request #5083

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/observability/MongoObservationCommandListenerTests.java

@@ -31,6 +31,7 @@ import reactor.core.publisher.BaseSubscriber;
 import org.assertj.core.api.Assertions;
 import org.bson.BsonDocument;
 import org.bson.BsonString;
+import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
@@ -72,6 +73,15 @@ class MongoObservationCommandListenerTests {
 		this.listener = new MongoObservationCommandListener(observationRegistry);
 	}
 
+	@AfterEach
+	void tearDown() {
+		Observation currentObservation = observationRegistry.getCurrentObservation();
+		if (currentObservation != null) {
+			currentObservation.stop();
+			observationRegistry.setCurrentObservationScope(null);
+		}
+	}
+
 	@Test
 	void commandStartedShouldNotInstrumentWhenAdminDatabase() {