`ILogger` is deprecated and will be removed

[susnux]

The ILogger interface is deprecated and its logging functions will be removed with Nextcloud 31.
Please migrate to the PSR LoggerInterface. The logging levels inside ILogger will remain, but we recommend to use the logging levels provided by PSR-3.

Code reference:

files_texteditor/lib/Controller/FileHandlingController.php

Line 42 in e3a3cec

/** @var ILogger */

files_texteditor/tests/Controller/FileHandlingControllerTest.php

Line 49 in e3a3cec

/** @var ILogger|\PHPUnit_Framework_MockObject_MockObject */