Unfortunately, Git-TF currently is not able to use the KeyChain secure storage on Mac.
You may add user name and password to the Git configuration file. In the
directory of your repository in the
file find the
section and add two new parameters
collection = http://...
serverpath = $/...
username = your-user-name
password = your-password
Note that, if you add only the
parameter, you still will be prompt for a password.