fix: Avoid symlinks for user-docs venv creation

[wulmer]

There was/is an issue with the creation and caching of the Python virtual environment.

When we create it with uv or python3 -m venv, the python executable is only linked to the system's Python installation.

This symlink is not properly cached in the GitHub cache action.

The workaround is to use the --copies flag for venv, however there is no equivalent flag for uv, although there is a similar one for linking cached Python libraries (--link-mode).

Unless astral-sh/uv#6782 is fixed soon, we have to live with the workaround of using good old venv.

P.S.: the build still fails for this PR as we are using pull_request_target.

[github-actions]

Code Coverage Report

Project	Statements Rate	Branch Rate	Indicator
packages/autopilot-utils	96.67%	90.23%	💚
dist/coverage/python	96.67%	90.23%	💚
apps/splunk-fetcher	92.51%	82.00%	💚
apps/sharepoint-fetcher	84.83%	76.62%	💚
apps/sharepoint-evaluator	94.09%	90.48%	💚
apps/sharepoint	83.98%	67.86%	💚
apps/security-scanner	0.00%	0.00%	💔
apps/pex-tool	93.07%	78.05%	💚
apps/pdf-signature-evaluator	67.48%	48.80%	💛
apps/papsr	98.25%	94.74%	💚
apps/filecheck	98.53%	96.30%	💚
apps/excel-tools	78.37%	62.89%	💛
apps/artifactory-fetcher	98.51%	92.86%	💚
Total	87.13%	75.70%	💚