docs: public synchronized void unregisterSessionManager(Object key) {
          if (com.ibm.ejs.ras.TraceComponent.isAnyTracingEnabled() && LoggingUtil.SESSION_LOGGER_CORE.isLoggable(Level.FINE)) {
              LoggingUtil.SESSION_LOGGER_CORE.entering(methodClassName, methodNames[UNREGISTER_SESSION_MANAGER], "registryKey= " + key);
          }
          _genericSessionManagers.remove(key);
          if (com.ibm.ejs.ras.TraceComponent.isAnyTracingEnabled() && LoggingUtil.SESSION_LOGGER_CORE.isLoggable(Level.FINE)) {
              LoggingUtil.SESSION_LOGGER_CORE.exiting(methodClassName, methodNames[UNREGISTER_SESSION_MANAGER]);
          }
      }