Remove unused helper function

app/helpers.php

@@ -43,29 +43,6 @@ function formatDecimal($number)
 }
 
 /**
- * Format date in indonesian format dd-mm-yyyy.
- *
- * @param  string  $date
- * @return string
- */
-function formatDate($date)
-{
-    if (!$date || $date == '0000-00-00') {
-        return;
-    }
-
-    $explodedDate = explode('-', $date);
-
-    if (count($explodedDate) == 3 && checkdate($explodedDate[1], $explodedDate[0], $explodedDate[2])) {
-        return $explodedDate[2].'-'.$explodedDate[1].'-'.$explodedDate[0];
-    } elseif (count($explodedDate) == 3 && checkdate($explodedDate[1], $explodedDate[2], $explodedDate[0])) {
-        return $explodedDate[2].'-'.$explodedDate[1].'-'.$explodedDate[0];
-    }
-
-    throw new App\Exceptions\InvalidDateException('Invalid date format.');
-}
-
-/**
  * Get Indonesian date format.
  *
  * @param  string  $date