As discussed in the Liberty Design Summit "Moving apps to Python 3"
cross-project workshop, the way forward in the near future is to
switch to the pure-python PyMySQL library as a default.
https://etherpad.openstack.org/p/liberty-cross-project-python3
Also set the OS_TEST_DBAPI_ADMIN_CONNECTION override variable so
that oslo.db opportunistic detection will know to use PyMySQL until
I12b32dc097a121bd43991bc38dd4d289b65e86c1 makes it the default
behavior.
Change-Id: Icd91a065d3c4f62791ba0dca99a822e3a1a0ad44
Co-Authored-By: Victor Sergeyev <vsergeyev@mirantis.com>
25f2c5e079