Don't flash 'current_password' input (#5541)

* Don't flash `current_password` input

With starter packs like Jetstream, the `current_password` input is used.

I believe that adding `current_password` to the `$dontFlash` list by default would help to ensure new projects follow security best practices from the get-go.

* Update Handler.php

Co-authored-by: Taylor Otwell <taylor@laravel.com>

app/Exceptions/Handler.php

@@ -22,6 +22,7 @@ class Handler extends ExceptionHandler
      * @var array
      */
     protected $dontFlash = [
+        'current_password',
         'password',
         'password_confirmation',
     ];