[4.4] copy api language files

[heelc29]

Pull Request for Issue #41944 .

Summary of Changes

Adds ability to place language files under api/language during installation of a component

<?xml version="1.0" encoding="UTF-8"?>
<extension type="component" method="upgrade">
	[...]
	<api>
		<files folder="api">
			<folder>src</folder>
		</files>
		<languages folder="api">
			<language tag="en-GB">language/en-GB/com_example.ini</language>
		</languages>
	</api>
</extension>

Testing Instructions

Add languages node under API in any component then test install/uninstall

Actual result BEFORE applying this Pull Request

language file is not copied

Expected result AFTER applying this Pull Request

language file is copied and deleted during uninstall

Link to documentations

Please select:

• [ ] Documentation link for docs.joomla.org: There is nothing special here https://docs.joomla.org/Manifest_files

• [ ] No documentation changes for docs.joomla.org needed

• [ ] Pull Request link for manual.joomla.org:

• [ ] No documentation changes for manual.joomla.org needed