Issue #3483587 by ptmkenny: Require PHP 8.3

.gitlab-ci.yml

composer.json

src/Form/FirebasePhpConfigurationForm.php

src/Form/FirebasePhpSendTestMessageForm.php

src/Form/FirebasePhpValidateTokenForm.php

src/Service/FirebasePhpMessagingApi.php

tests/src/Kernel/FirebasePhpInstallTest.php