Xdebug memory and performance issues

[derschatta]

Describe the bug
Xdebug on the latest version (3.3.2) is very slow (updated in #290). In addition the latest images run out of PHP memory from the get go. This is probably due to the changes made in #279.

To Reproduce
Steps to reproduce the behavior:

1. Download the latest images
2. Open a site with the -debug container

Expected behavior
It works and is reasonably well performing.

Screenshots
There's an error that PHP memory is exceeded (default is 256MB). Also even if you increase the memory in php.ini it is very slow to load.