eclass: Upgrade python eclasses to facilitate libxml2 upgrade.

This pulls the latest upstream copies of:
python-any-r1.eclass
python-r1.eclass
python-single-r1.eclass

BUG=chromium:1111336
TEST=CQ-passes

Cq-Depend: chromium:2328994,chromium:2341088,chromium:2341089
Change-Id: Ifbeaa01ef855aaeb87a5f28042557650501ef79c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/2329147
Tested-by: Allen Webb <allenwebb@google.com>
Commit-Queue: Allen Webb <allenwebb@google.com>
Reviewed-by: Alex Klein <saklein@chromium.org>
3 files changed