MM-16258: Adds new API endpoint + (App & Client & Store) to retrieve … (#11176)

* MM-16258: Adds new API endpoint + (App & Client & Store) to retrieve Users who would be removed from a list of hypothetical group IDs representing the synced groups.

* MM-16258: Adds roles to JSON response.

* MM-16258: Updates GetByIDs to use Squirrel.

* MM-16258: Puts as much as possible into Squirrel.

* MM-16258: Changes names of methods, functions, and route.

* MM-16258: Updates some comments.

* MM-16258: Extra validation of group_ids parameter.

* MM-16258: Changes validation of group_ids query param.

* MM-16258: Rename a variable and a constant.

* MM-16258: Fix test.

model/client4.go

@@ -4412,3 +4412,15 @@ func (c *Client4) PatchGroupSyncable(groupID, syncableID string, syncableType Gr
 	defer closeBody(r)
 	return GroupSyncableFromJson(r.Body), BuildResponse(r)
 }
+
+func (c *Client4) TeamMembersMinusGroupMembers(teamID string, groupIDs []string, page, perPage int, etag string) ([]*UserWithGroups, int64, *Response) {
+	groupIDStr := strings.Join(groupIDs, ",")
+	query := fmt.Sprintf("?group_ids=%s&page=%d&per_page=%d", groupIDStr, page, perPage)
+	r, err := c.DoApiGet(c.GetTeamRoute(teamID)+"/members_minus_group_members"+query, etag)
+	if err != nil {
+		return nil, 0, BuildErrorResponse(r, err)
+	}
+	defer closeBody(r)
+	ugc := UsersWithGroupsAndCountFromJson(r.Body)
+	return ugc.Users, ugc.Count, BuildResponse(r)
+}