Bump Python 3 packages version for FreeBSD
Summary:
Most packages are now built for Python 3.7 in binary packages.
Fixes T1570.
Test Plan: salt windriver state.sls_id install_salt_extra_software roles/saltmaster
Reviewers: dereckson
Reviewed By: dereckson
Maniphest Tasks: T1570
Differential Revision: https://devcentral.nasqueron.org/D2150