This was bugging me for quite some time. Sometimes there would be some notices in the Notification tab.
It was hard in the beginning to find which project was triggering that.
In my day to day life I use phpstorm and by pressing CTRL+T it would pull all the changes by making git pull for all git repositories that were configured in the current project.
Mike Airey suggested a working fix by running the following commands that will stop the Bitbucket authentication prompt.
It was annoying because it didn't remember that the authorization was done and it kept prompting every single time.
You need to run this in a cmd or terminal window or within the terminal window of phpstorm/jetbrain apps.
git config --global --replace-all credential.interactive false git config --global --replace-all credential.modalPrompt false