We have removed the option to add enable/disable/default-enable/default-disable files, so this is no longer an override

Commit 1edc1264 replaced Travis CI with GitHub Actions. These are
configured through the `.github` directory.

Commit 1edc1264 replaced Travis CI with GitHub Actions. Remove the
remaining references to Travis CI.

* Start testing on PHP 8.0

* Update test-framework

* Fix broken unit tests

* Fix query; apparently under PHP8 the query would raise PDOException instead of returning false

Co-authored-by: Tim van Dijen <tvdijen@gmail.com>