Fix indentation in wp_checkdate function

Author: pbearne

src/wp-includes/functions.php

@@ -7399,9 +7399,9 @@ function wp_is_stream( $path ) {
 function wp_checkdate( $month, $day, $year, $source_date ) {
 
 	$checkdate = false;
-    if ( is_numeric( $month ) && is_numeric( $day ) && is_numeric( $year ) ) {
-             $checkdate = checkdate( intval( $month ), intval( $day ), intval( $year ) );
-     }
+	if ( is_numeric( $month ) && is_numeric( $day ) && is_numeric( $year ) ) {
+		$checkdate = checkdate( intval( $month ), intval( $day ), intval( $year ) );
+	}
 	/**
 	 * Filters whether the given date is valid for the Gregorian calendar.
 	 *