CVE-2023-5752: Command Injection in pip when used with Mercurial

When installing a package from a Mercurial VCS URL (ie “pip install hg+…”) with pip prior to v23.3, the specified Mercurial revision could be used to inject arbitrary configuration options to the “hg clone” call (ie “–config”). Controlling the Mercurial configuration can modify how and which repository is installed. This vulnerability does not affect users who aren’t installing from Mercurial.