Add missing PDO_SQLITE constants to documentation

[lacatoire]

📝 Description de la Pull Request

This PR adds missing constants for the PDO_SQLITE driver that are currently available in PHP but not documented.

Issue: https://github.com/php/doc-en/issues/1394

Newly added constants:

PDO::SQLITE_ATTR_OPEN_FLAGS
PDO::SQLITE_OPEN_READONLY
PDO::SQLITE_OPEN_READWRITE
PDO::SQLITE_OPEN_CREATE
PDO::SQLITE_ATTR_READONLY_STATEMENT
PDO::SQLITE_ATTR_EXTENDED_RESULT_CODES
PDO::SQLITE_DETERMINISTIC