Sharing Repo with Group


My team has a couple of repos we want to share with other developers, without giving them access to our entire team as well as without giving access to each repo individually (that would take a lot of time).

It seems this is the solution:

However, when I go to any repo > settings > members, I don’t see the share with group tab like that screenshot shows. This is all I see:

What am I missing? Please help! (Please note I have Owner access.)

Thank you!