Fix test

Author: acogoluegnes

deps/rabbit/test/rabbit_stream_sac_coordinator_SUITE.erl

@@ -78,7 +78,8 @@ ensure_monitors_test(_) ->
                                                       State0,
                                                       Monitors0,
                                                       []),
-    ?assertEqual(1, sets:size(PidsGroups)),
+    ?assertEqual(1, maps:size(PidsGroups)),
+    ?assertEqual(1, sets:size(maps:get(self(), PidsGroups))),
     ?assertEqual(#{self() => {self(), sac}}, Monitors1),
     ?assertEqual([{monitor, process, self()}, {monitor, node, node()}],
                  Effects1),