Release 3.1.0

What's Changed

• Fix CI (add --no-ansi to poetry install) by @ishiy1993 in #30
• Update ssh key by @ishiy1993 in #31
• Drop python 3.6 by @amutake in #33
• Bump version 3.1.0 by @amutake in #34

New Contributors

• @amutake made their first contribution in #33

Full Changelog: release-3.0.0...release-3.1.0