What happened at the end of the movie The Nun?

In the movie "The Nun," the character Father Burke sacrifices himself to defeat the demon Valak, ultimately banishing it back to Hell. Sister Irene and Frenchie survive the ordeal and are shown leaving the monastery together. The film ends with a shot of the blood-covered painting of Valak, hinting that it may not be the last we see of the malevolent spirit.