Version 2.1.3

Drop "support" for python 3.8, it never worked in the first place. Fixed to only support python 3.9 and up.
Changed to using ruff instead of flake8, and added a bunch of extra checks because it's so easy to do so with ruff.
Added python 3.9 to github actions run matrix to ensure we maintain python 3.9 compatibility in the future.
Update a bunch of dependencies.

What's Changed

• [pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in #18
• [pip prod] (deps): Bump werkzeug from 2.2.3 to 2.3.2 by @dependabot in #19
• [pip dev] (deps-dev): Bump tox from 4.4.12 to 4.5.1 by @dependabot in #20
• [pip prod] (deps): Bump werkzeug from 2.3.2 to 2.3.3 by @dependabot in #21
• [pip dev] (deps-dev): Update mypy requirement from ~=1.2.0 to ~=1.3.0 by @dependabot in #22
• [pip dev] (deps-dev): Update flake8-bugbear requirement from ~=23.3.23 to ~=23.5.9 by @dependabot in #23
• [pip dev] (deps-dev): Update pytest-cov requirement from ~=4.0.0 to ~=4.1.0 by @dependabot in #24
• [pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in #25
• [pip dev] (deps-dev): Update flake8-bugbear requirement from ~=23.5.9 to ~=23.6.5 by @dependabot in #26
• [pip dev] (deps-dev): Update tox requirement from ~=4.5.1 to ~=4.6.0 by @dependabot in #27
• [pip dev] (deps-dev): Update pillow requirement from ~=9.5.0 to ~=10.0.0 by @dependabot in #30
• [pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in #31
• [pip dev] (deps-dev): Update flake8-bugbear requirement from ~=23.6.5 to ~=23.7.10 by @dependabot in #32
• [pip dev] (deps-dev): Update black requirement from ~=23.3.0 to ~=23.7.0 by @dependabot in #33
• [pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in #34

Full Changelog: v2.1.0...v2.1.3