Cron API: Correct the documented type and value of the $doing_wp_cron variable.

See #63166

git-svn-id: https://develop.svn.wordpress.org/trunk@60653 602fd350-edb4-49c9-b593-d223f7449a82

Author: johnbillion

src/wp-includes/cron.php

@@ -940,7 +940,7 @@ function spawn_cron( $gmt_time = 0 ) {
 	 *     An array of cron request URL arguments.
 	 *
 	 *     @type string $url  The cron request URL.
-	 *     @type int    $key  The 22 digit GMT microtime.
+	 *     @type string $key  The Unix timestamp (UTC) of the cron lock with microseconds.
 	 *     @type array  $args {
 	 *         An array of cron request arguments.
 	 *
@@ -949,7 +949,7 @@ function spawn_cron( $gmt_time = 0 ) {
 	 *         @type bool $sslverify Whether SSL should be verified for the request. Default false.
 	 *     }
 	 * }
-	 * @param string $doing_wp_cron The Unix timestamp (UTC) of the cron lock.
+	 * @param string $doing_wp_cron The Unix timestamp (UTC) of the cron lock with microseconds.
 	 */
 	$cron_request = apply_filters(
 		'cron_request',