Cron API: Clarify documentation for `wp_reschedule_event()`.

Expands documentation to indicate `wp_schedule_event()` ought to be used for rescheduling an upcoming event, while `wp_reschedule_event()` is used for internally rescheduling a recurring event after it runs.

Props Dharm1025, jrf.
Fixes #35968.



git-svn-id: https://develop.svn.wordpress.org/trunk@43608 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/cron.php

@@ -197,11 +197,17 @@ function wp_schedule_event( $timestamp, $recurrence, $hook, $args = array() ) {
 /**
  * Reschedules a recurring event.
  *
+ * Mainly for internal use, this takes the time stamp of a previously run
+ * recurring event and reschedules it for its next run.
+ *
+ * To change upcoming scheduled events, use {@see wp_schedule_event} to
+ * change the recurrence frequency.
+ *
  * @since 2.1.0
  * @since 5.0.0 Return value modified to boolean indicating success or failure,
  *              {@see pre_reschedule_event} filter added to short-circuit the function.
  *
- * @param int    $timestamp  Unix timestamp (UTC) for when to next run the event.
+ * @param int    $timestamp  Unix timestamp (UTC) for when the event was scheduled.
  * @param string $recurrence How often the event should subsequently recur. See wp_get_schedules() for accepted values.
  * @param string $hook       Action hook to execute when the event is run.
  * @param array  $args       Optional. Array containing each separate argument to pass to the hook's callback function.