chore(dev): add xdebug support for docker setup

[bourdaisj]

Add xdebug support in the docker compose setup.
Works well with my my setup (vscode), should work fine for other IDE as well.

If this looks good, I will provide documentation in the README.md and other relevant places (?).

[ssddanbrown]

Thanks for this @Julesdevops,
Have tested on a PHPStorm setup and it seems to work well.

I did notice that the xdebug.start_with_request=yes which will activate xdebug on every request which will slow things down a bit when debugging. Probably notthing to worry about now but if people report slow development environments using the docker setup, this might need to change to be manually/extension initiated instead.

In regards to any documentation, keep it brief/high-level where possible. Don't want to fill the readme with instructions for each possible editor or anything.

[bourdaisj]

@ssddanbrown Thx for feedback, I updated the readme.
Agree for the start_with_request option. I will be here to improve it if contributors reports slow development environments. :)

[ssddanbrown]

Now merged, thanks again @Julesdevops

[esakkiraja100116]

#4187 - Can you look at this issue @Julesdevops ?