Editor: Define $suffix before using it in _WP_Editors::print_tinymce_scripts().

Props imath.
Fixes #40479. See #35760.

git-svn-id: https://develop.svn.wordpress.org/trunk@40477 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-wp-editor.php

@@ -1331,6 +1331,7 @@ final class _WP_Editors {
 			script_concat_settings();
 		}
 
+		$suffix = SCRIPT_DEBUG ? '' : '.min';
 		$version = 'ver=' . $tinymce_version;
 		$baseurl = self::get_baseurl();