Eg
curl -i -X POST -d '{"requests":["?idsite=1&rec=1&idgoal=21&apiv=1&_id=50d60fcd18ff0c7e&cdt=1610168419&revenue=0&send_image=0","?idsite=1&rec=1&idgoal=21&apiv=1&_id=50d60fcd18ff0c7e&cdt=1610168419&revenue=0&send_image=0"]}' http://your.site/matomo.php
Can trigger an HTTP 500 error when the request is authenticated (or when using a recent timestamp). That's because when for example A/B tests are configured, then it does a Date::factory($request->getCurrentTimestamp))
where the timestamp is a string
and thus the Date class would trigger an exception.
Making sure we return an integer will fix all possible uses.