[5.3] Fix 'remember_me' column not found error

[srmklive]

Fixes #16509.

Currently if the user removes the remember_token field from the table, exception is thrown when the user tries to logout from the system. This PR adds a remember_column variable to the Authenticatable trait. If the user remember_token field from the database, exception upon logout can be avoided by overriding the $remember_column value in the App\User model as:

protected $remember_column = '';