docs: public static boolean unregisterSASLMechanism(String clazz) {
          synchronized (REGISTERED_MECHANISMS) {
              Iterator<SASLMechanism> it = REGISTERED_MECHANISMS.iterator();
              while (it.hasNext()) {
                  SASLMechanism mechanism = it.next();
                  if (mechanism.getClass().getName().equals(clazz)) {
                      it.remove();
                      return true;
                  }
              }
          }
          return false;
      }