Ignore msg_stores in virginity check

msg_stores is a potential mount point and therefore might exist

Author: mkuratczyk

deps/rabbit/src/rabbit_mnesia.erl

@@ -1042,6 +1042,7 @@ mnesia_and_msg_store_files() ->
              rabbit_node_monitor:coordination_filename(),
              rabbit_node_monitor:stream_filename(),
              rabbit_node_monitor:default_quorum_filename(),
+             rabbit_node_monitor:classic_filename(),
              rabbit_node_monitor:quorum_filename(),
              rabbit_feature_flags:enabled_feature_flags_list_file(),
              rabbit_khepri:dir()],

deps/rabbit/src/rabbit_node_monitor.erl

@@ -14,6 +14,7 @@
          cluster_status_filename/0, coordination_filename/0,
          stream_filename/0,
          quorum_filename/0, default_quorum_filename/0,
+         classic_filename/0,
          prepare_cluster_status_files/0,
          write_cluster_status/1, read_cluster_status/0,
          update_cluster_status/0, reset_cluster_status/0]).
@@ -83,6 +84,9 @@ quorum_filename() ->
 default_quorum_filename() ->
     filename:join(rabbit:data_dir(), "quorum").
 
+classic_filename() ->
+    filename:join(rabbit:data_dir(), "msg_stores").
+
 -spec prepare_cluster_status_files() -> 'ok' | no_return().
 
 prepare_cluster_status_files() ->