chore: Upgrade dependencies (#3830)

* wip: laraval and symfony upgrades

* Apply fixes from StyleCI

* Apply fixes from StyleCI

* bump var dumper to 6.3

* require guzzle 7.7

* remove docbloc

* lock symfony/translation-contracts to 2.5

* fix: require mailgun package

* remove docblock

* fix: flysystem tests

* fix: instance flarum assets for testing

* Apply fixes from StyleCI

* downgrade intervention/image back to 2.x

* Apply fixes from StyleCI

* provide ImageManager to AvatarUploader

* fix larastan

* revert back some other intervention/image changes

* fix image resize

* Update framework/core/src/Http/Middleware/AuthenticateWithHeader.php

Co-authored-by: Daniël Klabbers <luceos@users.noreply.github.com>

* Apply fixes from StyleCI

* Update framework/core/src/Mail/SmtpDriver.php

Co-authored-by: Sami Mazouz <sychocouldy@gmail.com>

* Update framework/core/src/User/LoginProvider.php

Co-authored-by: Sami Mazouz <sychocouldy@gmail.com>

* use named attrs

* revert imagemanager in constructor

* revert to using Contract mailer

* reinstate and update FlarumLogTransport

* correct var typo, use one less temp var

* names attrs

* uncomment test

* mailer contract

* Apply fixes from StyleCI

---------

Co-authored-by: StyleCI Bot <bot@styleci.io>
Co-authored-by: Daniël Klabbers <luceos@users.noreply.github.com>
Co-authored-by: Sami Mazouz <sychocouldy@gmail.com>

extensions/flags/src/Flag.php

@@ -31,7 +31,7 @@ class Flag extends AbstractModel
 {
     use ScopeVisibilityTrait;
 
-    protected $dates = ['created_at'];
+    protected $casts = ['created_at' => 'datetime'];
 
     public function post(): BelongsTo
     {