Актуально для пакетов:

php8.2-swoole-6.0.1-alt2.27
php8.3-swoole-6.0.1-alt2.17
php8.4-swoole-6.0.1-alt2.4

Шаги воспроизведения:

# apt-get install php8.{2,3,4} php8.{2,3,4}-swoole
$ for v in 2 3 4; do echo "check php8.$v"; php8.$v -m | grep swoole; done

Получаемый результат:

check php8.2
PHP Warning:  Cannot load module "swoole" because required module "mysqlnd" is not loaded in Unknown on line 0
check php8.3
PHP Warning:  Cannot load module "swoole" because required module "mysqlnd" is not loaded in Unknown on line 0
check php8.4
PHP Warning:  Cannot load module "swoole" because required module "mysqlnd" is not loaded in Unknown on line 0

Установка пакета php8.$v-mysqlnd для соответствующей версии php решает проблему.