Changes to Follow or unfollow a user (toggle)

api operation id toggleFollowUsers was added

for the path request parameter user_id, the type was generalized from integer to string

added the non-success response with the status 401

added the non-success response with the status 403

added the non-success response with the status 404

added the non-success response with the status 500

added the non-success response with the status 400

endpoint added

api path removed without deprecation