Single space Guest access default user group is not created automatically

Issue Summary

Single space Guest access default user group is not created automatically

Steps to Reproduce

1. Go to settings >> global permissions >> guest access
   Try to invite a guest user to a site and it will throw an error

Expected Results

A group with default access should be present for Guest users.

Actual Results

No guest access group gets created and thus unable to invite guest users.

Workaround

Create a group manually for guest access and make it a default access group.