Add first battery of e2e tests for PHP

[ereslibre]

Add a first battery of simple PHP scripts that are executed with the PHP runtime built to WebAssembly. The result and timing of execution should be compared to the same PHP version, but built for a common architecture, such as x86_64.

Additionally, fuzzing could be added to this tests, so that we are able to detect error conditions that only happen in the wasm32-wasi target and not in a common architecture such as x86_64.

[jedjones-uk]

Please include at least one of the major frameworks doing simple operations. It's more than just a script but will represent a far better real world picture of the potential users. Anyone in the PHP world exploring a Wasm Based runtime is not going to be just writing a script or so.

https://symfony.com/
https://laravel.com/

These are probably the two biggest right now.