Add support for pass reset flood control variables

Patch in attachment

Updated patch with better default variables

Another update to include not only the ip, but also the user based flood variables for pass reset

Thanks for the patch, which is helpful for the Drupal 7 users out there.
We will not be putting effort into any more Drupal 7 releases, so I'll leave it as it is.

I checked how this works in Drupal 10, and as far as I can see there is no specific config for the password reset form (it uses general flood setting).

Feel free to re-open this issue, if you think there is any work that can be done for Drupal 10.