Update ThemingControllerTest.php

Adjusted test

apps/theming/tests/Controller/ThemingControllerTest.php

@@ -529,8 +529,8 @@ class ThemingControllerTest extends TestCase {
 			[UPLOAD_ERR_PARTIAL, 'The file was only partially uploaded'],
 			[UPLOAD_ERR_NO_FILE, 'No file was uploaded'],
 			[UPLOAD_ERR_NO_TMP_DIR, 'Missing a temporary folder'],
-			[UPLOAD_ERR_CANT_WRITE, 'Failed to write file to disk.'],
-			[UPLOAD_ERR_EXTENSION, 'A PHP extension stopped the file upload.'],
+			[UPLOAD_ERR_CANT_WRITE, 'Could not write file to disk'],
+			[UPLOAD_ERR_EXTENSION, 'A PHP extension stopped the file upload'],
 		];
 	}