Add a missing description for the `$_diff_threshold` property in the `WP_Text_Diff_Renderer_Table` class.

Props ipm-frommen.
Fixes #31008.


git-svn-id: https://develop.svn.wordpress.org/trunk@31295 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/wp-diff.php

@@ -42,7 +42,7 @@ class WP_Text_Diff_Renderer_Table extends Text_Diff_Renderer {
 	public $_trailing_context_lines = 10000;
 
 	/**
-	 * {@internal Missing Description}}
+	 * Threshold for when a diff should be saved or omitted.
 	 *
 	 * @var float
 	 * @access protected