Fix more deprecations

[javiereguiluz]

This is the last series of deprecations that I found in this package when upgrading an app to Symfony 5.4:

Since symfony/security-bundle 5.4: Method "Symfony\Bundle\SecurityBundle\DependencyInjection\SecurityExtension::addSecurityListenerFactory()" is deprecated, use "addAuthenticatorFactory()" instead.

Method "Symfony\Component\EventDispatcher\EventSubscriberInterface::getSubscribedEvents()" might add "array" as a native return type declaration in the future. Do the same in implementation "SymfonyCorp\Connect\Security\EventListener\LoginSuccessEventListener" now to avoid errors or add an explicit @return annotation to suppress this message.

Return type of SymfonyCorp\Connect\Api\Entity\AbstractEntity::offsetExists($index) should either be compatible with ArrayAccess::offsetExists(mixed $offset): bool, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice

Return type of SymfonyCorp\Connect\Api\Entity\AbstractEntity::offsetGet($index) should either be compatible with ArrayAccess::offsetGet(mixed $offset): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice

Return type of SymfonyCorp\Connect\Api\Entity\AbstractEntity::offsetSet($index, $value) should either be compatible with ArrayAccess::offsetSet(mixed $offset, mixed $value): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice

Return type of SymfonyCorp\Connect\Api\Entity\AbstractEntity::offsetUnset($index) should either be compatible with ArrayAccess::offsetUnset(mixed $offset): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice

SymfonyCorp\Connect\Api\Entity\User implements the Serializable interface, which is deprecated. Implement serialize() and unserialize() instead (or in addition, if support for old PHP versions is necessary)

[fabpot]

That beaks support for PHP 7.2 a,d 7.4. We might want to bump the min PHP version here?

[fabpot]

You should also update the Travis config to remove PHP 7.x from the test matrix.

[javiereguiluz]

This is now ready for the final review. Thanks!

[javiereguiluz]

If possible, please let's review this so we can merge and tag it (it's needed to update some applications to Symfony 6.x). Thanks!

[nicolas-grekas]

I force-pushed after squashing + adding one commit of mine.

[javiereguiluz]

Let's try to merge this and tag it as 8.0 the version bump will ensure that no existing app breaks because of these changes. Thanks!

[nicolas-grekas]

tagged v8.0.0