fix: revert rename changes

see #45250

Signed-off-by: Andy Scherzinger <info@andy-scherzinger.de>

build/files-checker.php

@@ -47,11 +47,11 @@ $expectedFiles = [
 	'__mocks__',
 	'__tests__',
 	'3rdparty',
-	'AUTHORS.md',
+	'AUTHORS',
 	'CHANGELOG.md',
 	'CODE_OF_CONDUCT.md',
 	'COPYING',
-	'COPYING-README.md',
+	'COPYING-README',
 	'DESIGN.md',
 	'Makefile',
 	'README.md',