PLT-6162: Search for users not in a given team. (#5943)

model/user_search.go

@@ -11,6 +11,7 @@ import (
 type UserSearch struct {
 	Term           string `json:"term"`
 	TeamId         string `json:"team_id"`
+	NotInTeamId    string `json:"not_in_team_id"`
 	InChannelId    string `json:"in_channel_id"`
 	NotInChannelId string `json:"not_in_channel_id"`
 	AllowInactive  bool   `json:"allow_inactive"`