Delete obsolete comment in RowMapperTests

Closes gh-23643

spring-jdbc/src/test/java/org/springframework/jdbc/core/RowMapperTests.java

@@ -78,7 +78,6 @@ public class RowMapperTests {
 	@AfterEach
 	public void verifyClosed() throws Exception {
 		verify(resultSet).close();
-		// verify(connection).close();
 	}
 
 	@AfterEach