Retry for delete team members

[dylan-smith]

We have retry on 404 when retrieving the team members (in create-team). This is to handle some apparent race condition where create team API returns successful, but trying to get the list of team members thinks the team doesn't exist yet.

We are getting a similar problem when trying to delete the team members (example here: https://github.com/github/gh-gei/runs/6673513988?check_suite_focus=true#step:16:181). We should do a similar retry on 404 when trying to delete the team members.