JAVA-27677: Reactivate core-java-os-2 and spring-6-rsocket (#15675)

spring-6-rsocket/pom.xml

@@ -49,6 +49,8 @@
 
     <properties>
         <spring-boot.version>3.1.3</spring-boot.version>
+        <org.slf4j.version>2.0.7</org.slf4j.version>
+        <logback.version>1.4.11</logback.version>
     </properties>
 
 </project>

spring-6-rsocket/src/test/java/com/bealdung/rsocket/RSocketRequestResponseIntegrationTest.java

@@ -28,7 +28,8 @@ public class RSocketRequestResponseIntegrationTest {
     @Test
     public void whenSendingStream_thenReceiveTheSameStream() {
         String message = "test message";
-        assertEquals(message, client.sendMessage(Mono.just(message))
+        String response = "test message,Response!";
+        assertEquals(response, client.sendMessage(Mono.just(message))
             .block());
     }