Update python
Update python

Changes:

- https://github.com/docker-library/python/commit/50850bb: Merge pull request https://github.com/docker-library/python/pull/647 from infosiftr/pin-pip-setuptools
- https://github.com/docker-library/python/commit/bb68424: Pin pip to 21.2.x and setuptools to 57.x
- https://github.com/docker-library/python/commit/57740ba: Update to 3.10.0rc2, pip 21.2.4
- https://github.com/docker-library/python/commit/aaacfe2: Update to 3.6.15, pip 21.2.4
- https://github.com/docker-library/python/commit/7d0f63b: Update to 3.7.12, pip 21.2.4

31z4/official-images,neo-technology/docker-official-images,neo-technology/docker-official-images,docker-solr/official-images,docker-library/official-images,neo-technology/docker-official-images,infosiftr/stackbrew,neo-technology/docker-official-images,docker-library/official-images,docker-library/official-images,31z4/official-images,infosiftr/stackbrew,thresheek/official-images,infosiftr/stackbrew,thresheek/official-images,31z4/official-images,docker-solr/official-images,docker-solr/official-images,neo-technology/docker-official-images,docker-library/official-images,docker-solr/official-images,31z4/official-images,31z4/official-images,docker-solr/official-images,docker-solr/official-images,31z4/official-images,thresheek/official-images,31z4/official-images,docker-library/official-images,thresheek/official-images,infosiftr/stackbrew,31z4/official-images,thresheek/official-images,docker-library/official-images,neo-technology/docker-official-images,thresheek/official-images,neo-technology/docker-official-images,docker-solr/official-images,31z4/official-images,31z4/official-images,docker-solr/official-images,infosiftr/stackbrew,docker-library/official-images,neo-technology/docker-official-images,31z4/official-images,docker-library/official-images,infosiftr/stackbrew,docker-solr/official-images,infosiftr/stackbrew,neo-technology/docker-official-images,thresheek/official-images,thresheek/official-images,thresheek/official-images,neo-technology/docker-official-images,31z4/official-images,thresheek/official-images,neo-technology/docker-official-images,docker-library/official-images,docker-solr/official-images,infosiftr/stackbrew,docker-solr/official-images,docker-library/official-images,neo-technology/docker-official-images,thresheek/official-images,docker-solr/official-images,31z4/official-images,docker-solr/official-images,thresheek/official-images,docker-library/official-images,neo-technology/docker-official-images,docker-library/official-images,infosiftr/stackbrew,infosiftr/stackbrew,infosiftr/stackbrew,infosiftr/stackbrew,infosiftr/stackbrew,neo-technology/docker-official-images,thresheek/official-images,docker-library/official-images,31z4/official-images,infosiftr/stackbrew,thresheek/official-images,docker-library/official-images,docker-solr/official-images