Where any actual waiver of the benefit of any covenant or condition in any lease on the part of any lessor or the lessor's heirs, executors, administrators, or assigns is proved to have taken place in any one particular instance, such actual waiver shall not be assumed, or deemed to extend to any instance or any breach of covenant or condition other than that to which such waiver specially relates, nor to be a general waiver of the benefit of any such covenant or condition unless an intention to that effect appears.