[PHP] Polish dockerfile

includes also #4839 because of --with-avif for gd configure command (is not available in 8.0)

contains the following adjustments:
- upgrade APCu to 5.1.22
- use PECL package for mailparse instead of git clone (3.1.4 is the latest one available and sice then no changes on master branch)
- split PECL commands into separate ones (according to https://hub.docker.com/_/php this is the recommended way)
- add missing configure options for gd extension to include webp, xpm and avif
- specify composer version to be installed
- cleanup more dev dependencies