In Wikipedia, I have read Goddess Kali killed two demons named Kolasura and Ghorasura. But, Is it true Goddess Kali killed Kolasura and Ghorasura? What was the story?
Yes that is true, both anecdotes appear from Yogini tantra.
The anecdote of Kolasur is mentioned in 17th chapter.
To narrate it in short. Vishnu was cursed by Brahma after the Linga incident. Thus, to get rid of it Vishnu started doing mantra jaap of Mahakali. Kali was pleased by it and appeared in front of Narayana. The twist is for leela alone, the curse of Brahma gets into motion. And an Asur named Kolasura comes out of heart of Vishnu who is malicious. He won over all there worlds and thus, devtas fell at the feet of Paramba Kalika ti be their saviour. She assured that she will kill Kolasura. And thus, she took the form of Brahmin Kumari. And asked Kolasur for food in his city Kolapura saying, "Oh king Im orphan and no one is to take care of me, kindly feed me." Kolasur took her to palace and started feeding her. Kali wasn't satisfied and asked for more. Kolasura said, "anything that satisfies your hunger kindly do that." She then engulfed the whole kingdom of Kolasura and finally even him, so that the devtas are relieved.(Another reason given is because Kolasur lusted for Kumari Kali). Thus, from that incident Kumari Puja (worshiping small girls) started in every household.
The Anecdote of Ghorasura is mentioned in chapter number 8.
Will put it in short too.
Once, Mahadeva and Mahadevi were roaming in universe. Shiva decided to play pun on Devi. He said, "oh devi the whole universe is annihilated by me thus, we have no place to sit. Kindly think of any place so that we can rest." Devi, became angry and spoke, "Oh shiva Im eternal truth and consciousness, it is by me that tridevas create, sustain and destory, it is me who created you as my son (here devi is addressing herself as Trimurti Janani, not to be taken otherwise). Without me you are Shava(dead corpse)." The story says Shiva was infuriated by these words of devi. And thus he felt sad for himself. He decided to take revange on devi. Thus, in the western part of universe he created Ghorasura from his body ashes. Ghorasura was a huge demon as the ancedote describes him. Shiva then instructed him to stay there and kill Mahadevi when she comes there. Once, devi said to Shiva, after creation she hasn't seen the universe and thus want to go to see it. Shiva says let's go to the western part(knowingly he said so). Thus, upon resching there, devi was enchanted by the beauty of the place and she started roaming there. Ghorasura saw devi and lusted for her. He dared to ask Devi to marry him. Devi said, she will marry him only if he could win over her because that was an oath she took earlier. Soon, the war started between Kali and Ghorasura. Thousands of years passed away but Ghorasura couldn't win against mata. Finally, he started engulfing the universe out of frustration. Kali was infuriated at this action and thus she said, "Oh Asur, listen. I'm the one who is the cause of the universe and how dare you try to destroy it." Then Kali gives him the upadesh of her tatwa. Later Kali says,"Oh Ghorasura, since u served me for so many years (mata is so much compassinate that she considered even the war by Ghorasura as a seva to her🥺) and earlier you had asked me to marry you, and now that you know completely my Kali tatwa, you are indeed Shiva." To cut short, she gobbles up Ghorasura and eats him with her dreadful teeth. (Don't think Ghorasura was devotee or something, it's only the Karuna of Kali that she imparted the knowledge and tatwa to Ghorasura and finally merged him back into her.)
One might think, why did Kali taught Ghorasura her Tatwa, if she finally had to eat him?
The reason is simple, because, Mahakali wanted us mortals to know her tatwa via her ancedote here. So, that we too like Ghorasura can merge back into the Karunamurti Kali. Such are two of the innumerable the divine plays of Kali.