chore(phpstan): enable phpstan in bundled extensions (#3667)

* feat(phpstan): pick up extended model relations typings
* feat(phpstan): pick up extended model date attributes
* feat(core): introduce `castAttribute` extender
Stops using `dates` as it's deprecated in laravel 8
* feat(phpstan): pick up extended model attributes through casts
* fix: extenders not resolved when declared namespace
* fix(phpstan): new model attributes are always nullable
* chore(phpstan): add helpful cache clearing command
* Apply fixes from StyleCI
* chore: improve extend files provider logic
* chore: rename `castAttribute` to just `cast`
* chore: update phpstan package to detect `cast` method
* chore: enable phpstan in bundled extensions
* chore: rebasing conflicts
* chore: rebasing conflicts
* chore: typings for latest 1.7 changes

Signed-off-by: Sami Mazouz <sychocouldy@gmail.com>

extensions/suspend/extend.php

@@ -34,7 +34,9 @@ return [
         ->css(__DIR__.'/less/admin.less'),
 
     (new Extend\Model(User::class))
-        ->dateAttribute('suspended_until'),
+        ->cast('suspended_until', 'datetime')
+        ->cast('suspend_reason', 'string')
+        ->cast('suspend_message', 'string'),
 
     (new Extend\ApiSerializer(UserSerializer::class))
         ->attributes(AddUserSuspendAttributes::class),