What is the authenticity of the story about Ali ibn Abi Talib entering upon Umar ibn al-Khattab at night in the treasury, and asking him whether the matter concerned religion or worldly affairs, whereupon he extinguished the lamp if the matter concerned worldly affairs?

The mentioned report has not been narrated, but a similar report about Umar ibn Abd al-Aziz has been narrated by Amr ibn Muhajir, Umar's guard. He said that Umar would have a candle lit for the needs of the Muslims, and when he finished with them, he would extinguish it and light his own lamp.