[9.x] Add passwordTimeout to RequirePassword middleware as a parameter

[AlinIonut]

@driesvints as requested to master

This PR add the possibility to customize the RequirePassword middleware passwordTimeout duration, witch is retrieved from config default value at config('auth.password_timeout').

Example:

Route::get('/foo}', 'FooController@foo')->middleware(['password.confirm:password.confirm,60']);

'password.confirm' value parameter keeps the current possibility to customize desired redirect route.
'60' value parameter allow developers to customize passwordTimeout in seconds for each route as desired.

PS: This is my first PR to Laravel, soo please don't be to harsh, I'm learning to.
PS2: Initially I was thinking to preserve this logic with only one parameter (the current 'redirectToRoute') and check if is numeric, but I decided to keep it as simple as possible, and avoid conflicts with possible routes named as numeric.