Fix : PDO::exec returns a false equivalent (#157)

refector: Drop usage of xml_set_object() (#152)

Use proper callables instead.

Related to: php/php-src#12340

Co-authored-by: Konrad Abicht <hi@inspirito.de>

Huge cleanup (PHP 8 only; prep. for long term support) (#151)

* huge cleanup

* removed failing workflows for now

* switch to mariadb 11.0 and show db config

* mariadb 11.0 failed too; trying 10.5

* fixed bootstrap

* 2. attempt

* changed default table engine; fixed CI?

* refinements

* fixed failing tests

* removed further PDOSQLite related code

* salvaged old fixes and test

* re-added workflows; refined README

* refined adapter

* fixed get DB version code; added coding style workflow

* added DB specific adaptions

* fixed getServerVersion calls

* refined text

* reformat README

* README

* removed outdated ENV variable

* fixed coding style issue

Merge pull request #142 from ailintom/patch-1

Fixed store/ARC2_StoreEndpoint.php: $this has no property named $store

Merge pull request #137 from semsol/fix-tests

Upgrade vendors, fix tests (prepare version 2.5)