[3.8.x] [MNG-6889] Deprecate llr option (#1026)

* [MNG-6889] Big fat warning on llr

This option promotes "Maven2" in latest Maven 3 versions that is
insane. Also, this option was really meant to bridge transition
from Maven2 to Maven3, when both were sharing same local
repository. Hopefully, in 2023 nobody does that anymore.

---

https://issues.apache.org/jira/browse/MNG-6889

maven-core/src/main/java/org/apache/maven/internal/aether/DefaultRepositorySystemSessionFactory.java

@@ -241,6 +241,12 @@ private void setUpLocalRepositoryManager( MavenExecutionRequest request, Default
                 session.setLocalRepositoryManager( simpleLocalRepoMgrFactory.newInstance( session, localRepo ) );
                 logger.info( "Disabling enhanced local repository: using legacy is strongly discouraged to ensure"
                                  + " build reproducibility." );
+                logger.warn( "" );
+                logger.warn( "Due issues listed above, but also due fact that with this option Maven" );
+                logger.warn( "cannot provide the latest local repository features, it is being DEPRECATED." );
+                logger.warn( "Moreover, this option is being DROPPED starting with Maven 3.9.1, and use" );
+                logger.warn( "of this option will prevent Maven execution." );
+                logger.warn( "" );
             }
             catch ( NoLocalRepositoryManagerException e )
             {