bug(docker): pip_install_keeping_cached_packages misses --no-cache

[sersorrel]

The pip_install_keeping_cached_packages check looks only for --no-cache-dir, but ignores the fact that pip lets you abbreviate its arguments, so --no-cache works just as well.

Expected Behavior

pip install --no-cache should be sufficient to silence the warning: --no-cache is an abbreviation of --no-cache-dir. (Even --no-ca would work; --no-c is ambiguous with e.g. --no-color)

I suppose there's an argument that KICS should not encourage usage that could theoretically become ambiguous with a new version of pip, if the pip authors add a --no-cache-update argument or something, but this specific shortening seems pretty widely used – of 406k GitHub code search results for pip install "--no-cache", up to 109k of them appear to use the shortened form (pip install "--no-cache" NOT "--no-cache-dir").

Actual Behavior

KICS complains that "When installing packages with pip, the '--no-cache-dir' flag should be set to make Docker images smaller".

Steps to Reproduce the Problem

FROM python:3.12
RUN pip install --no-cache .

Specifications

(N/A if not applicable)

• Version: "GitLab kics analyzer v4.2.1"
• Platform: Linux amd64
• Subsystem: Docker