Add gdbinit files for php 8.0 and 8.1

[labbati]

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[bwoebi]

What do you need these for? As in, when isn't it enough to do source /usr/local/src/php/.gdbinit in gdb in our containers?

[labbati]

For cases when you have not PHP's sources, but you mount dd-trace-php, e.g. our dd-trace-php-solutions repo, randomized tests and rel-env images.

If we want to remove them it is not a big deal (I can wget them, no problem) but we should either remove them for all versions in that folder or to have them for all versions.

[bwoebi]

Ah we already have existing gdbinit files (never seen those), then it's a no-brainer :-)

[labbati]

Thanks