[MM-24334] Include role filtering in ES search (#14465)

* ES supports role filtering for users

- Added roles field for ES user index
- Include role filtering logic in ES

model/user.go

@@ -124,6 +124,7 @@ type UserForIndexing struct {
 	Nickname    string   `json:"nickname"`
 	FirstName   string   `json:"first_name"`
 	LastName    string   `json:"last_name"`
+	Roles       string   `json:"roles"`
 	CreateAt    int64    `json:"create_at"`
 	DeleteAt    int64    `json:"delete_at"`
 	TeamsIds    []string `json:"team_id"`