Docs: Add a @since note to edit_comment() about the new return value.

Follow-up to [48154].

See #39732.

git-svn-id: https://develop.svn.wordpress.org/trunk@48223 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/comment.php

@@ -45,6 +45,10 @@ function comment_exists( $comment_author, $comment_date, $timezone = 'blog' ) {
  * Update a comment with values provided in $_POST.
  *
  * @since 2.0.0
+ * @since 5.5.0 A return value was added.
+ *
+ * @return int|WP_Error The value 1 if the comment was updated, 0 if not updated.
+ *                      A WP_Error object on failure.
  */
 function edit_comment() {
 	if ( ! current_user_can( 'edit_comment', (int) $_POST['comment_ID'] ) ) {