[PHP] Reuse build files from setup-php action

Currently, the PHP feature builds PHP from source code which can take a while and does not contain any PHP extension.

Maybe it makes sense here to reuse the build binaries from the popular setup-php action:

https://github.com/shivammathur/php-builder/releases

So instead of building it from source, we download the tar and unpack it

Start by tracing the PHP feature's existing source-build entry point and compare it with the PHP builder release tar referenced in the issue. Confirm how the archive should be downloaded and unpacked, including extension availability, and consider the work done when the feature installs PHP without compiling it from source.

Written by the indexing model from the issue text.