Bump python from 3.8.5-slim-buster to 3.8.6-slim-buster
Bump python from 3.8.5-slim-buster to 3.8.6-slim-buster

Bumps python from 3.8.5-slim-buster to 3.8.6-slim-buster.

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
lsst-sqre/ltd-keeper,lsst-sqre/ltd-keeper