[CI SKIP] improvements to CONTRIBUTING.md (#3544)
[CI SKIP] improvements to CONTRIBUTING.md (#3544)

* [CI SKIP] improvements to CONTRIBUTING.md

* [CI SKIP] correct code flavor

* [CI SKIP] put Source classes in a table

* [CI SKIP] add info

* Update CONTRIBUTING.md

* [CI SKIP] add tachiyomi 0.8.5 link

* [CI SKIP] change link

* Update CONTRIBUTING.md

Co-authored-by: arkon <7e49b8fd5be7ecce7508ac4773898ceee838da34@users.noreply.github.com>
inorichi/tachiyomi-extensions,inorichi/tachiyomi-extensions,inorichi/tachiyomi-extensions