I have noticed a job announcement with title Project Manager in Ice Breaker Team in a software company.
What does Ice Breaker Team mean?
You should ask the employer. Only they can know the answer. The description of the job is more important, as well as the benefits.
It can mean anything:
Best guess: This is simply the name of the team within the company. The company might use it to identify that team and might have thought it sounds cool enough to use in their job ad.
The name might or might not also tell a bit about what they do. Looking at the job ad (yes it's apparently easy enough to google it), this is a customer facing team where "You will be part of demonstrator projects with latest technology" - so the name might refer to breaking the ice with new customers.