[PRQ#51944] Merge Request for python-m2r

MarsSeed [1] filed a request to merge python-m2r [2] into python-m2r2 [3]: m2r's upstream is dead. m2r2 is the backwards-compatible successor fork. No negative impact to this merge: python-dephell is long dead, its repo is archived. And it was only used by a few Python packages to convert pyproject.toml backwards to deprecated executable setup.py, which shall no longer be done by any package. [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/python-m2r/ [3] https://aur.archlinux.org/pkgbase/python-m2r2/