[debugger] Add comment to DebuggerCommandImpl.kt

GitOrigin-RevId: 783de5c84f5ece84969cee0a71788b352174d6cf

java/debugger/impl/src/com/intellij/debugger/engine/events/DebuggerCommandImpl.kt

@@ -105,6 +105,7 @@ abstract class DebuggerCommandImpl(private val myPriority: PrioritizedTask.Prior
             notifyCancelled()
           }
         } finally {
+          // Command finished or postponed
           cancelCommandScope()
         }
       }