MM-10640 Set EnableUserCreation to true by default (#8815)

* Set EnableUserCreation to true by default

* Fix argument type to FormatBool

* Convert EnableUserCreation instances to pointer

* Convert to boolean in tests also

* Set value of pointer to be false

* Convert remaining EnableUserCreation instances to pointer

app/user_test.go

@@ -88,7 +88,7 @@ func TestCreateOAuthUser(t *testing.T) {
 
 	th.App.PermanentDeleteUser(user)
 
-	th.App.Config().TeamSettings.EnableUserCreation = false
+	*th.App.Config().TeamSettings.EnableUserCreation = false
 
 	_, err = th.App.CreateOAuthUser(model.USER_AUTH_SERVICE_GITLAB, strings.NewReader(json), th.BasicTeam.Id)
 	if err == nil {