I’d say something to her directly. Talk to your SM first about it and let them know the situation and that you’re going to coach her. Then, coach her on her poor attitude. If nothing changes, report her to your SM and let them handle it. Make sure other partners do the same as well so it doesn’t look like it’s just you that has an issue with her.

I'd remind your SM that a bunch of partners leaving or transferring is a separate issue from a difficult new partner, and the longer it goes unaddressed the less likely it is she will change her behavior; she's new, she needs to learn to play nice before it becomes her permanent behavior.

Edit: clarified text