Cursor offset and orientation arguments in StatementInterface::fetch() are deprecated

Cursor offset and orientation arguments in StatementInterface::fetch() are untested and likely not working.

Their usage is now triggering a deprecation, and the arguments will be removed in Drupal 12.

Before:

$connection->query("SELECT * FROM {node}")->fetch(FetchAs::Associative, 1, 1);

After:

$connection->query("SELECT * FROM {node}")->fetch(FetchAs::Associative);