Reduce image size - remove pip cache dir

[lap1nou]

Description

Greetings,

This PR aims to reduce the image size by more than 100 MB by removing pip / pipx / pip3 cache directory.

I'm not an expert but I think the pip cache directory is useless in our case since we aren't going to need them after on, so we don't care about them being cached.

I saw this trick from here: https://stackoverflow.com/questions/45594707/what-is-pips-no-cache-dir-good-for

Related issues

N / A

Point of attention

I tested a few package and it seems to work fine.

The cache is located in the folder /root/.cache/pip/ and while they are not present in the final image (they are probably cleaned up at some point but they still take some space because they are present in the layers of the image).

I would also say that there is 3 ways of getting rid of this cache:

• By adding the argument --pip-args="--no-cache-dir" or --no-cache-dir (if pip is directly used)
• By setting a environment variable PIP_NO_CACHE_DIR=1
• By removing the folder /root/.cache/pip/ after each steps (web, misc, osint, ...), in the bash script

I've only done this for the ad script for now, I will continue for other steps if you like this PR.

Regards.

[QU35T-code]

Thx @lap1nou ! Better if arguments are just after : pipx install and not at the end of the line (code compliance check)