[4.2] Fix move user to group

[heelc29]

Summary of Changes

The feature to move an user to a group is broken after #38596.

Variable $users is not assigned in this if-case. Use the correct variable $userIds like it was before #38596

joomla-cms/administrator/components/com_users/src/Model/UserModel.php

Lines 725 to 727 in f520c98

	// Remove users from the group
	$query->delete($db->quoteName('#__user_usergroup_map'))
	->whereIn($db->quoteName('user_id'), $userIds);

Testing Instructions

Try moving a user to a group using the batch command.

Actual result BEFORE applying this Pull Request

Expected result AFTER applying this Pull Request

The user is moved to the new group.

Link to documentations

Please select:

• No documentation changes for docs.joomla.org needed
• No documentation changes for manual.joomla.org needed

[alikon]

I have tested this item ✅ successfully on e3326d8

---

_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/39483.}

[ceciogit]

I have tested this item ✅ successfully on e3326d8

---

_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/39483.}

[richard67]

RTC

---

_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/39483.}

[wilsonge]

Thanks!