Remove discord from project docs

CONTRIBUTING.md

@@ -20,11 +20,6 @@ interesting and leave a comment that you're beginning to investigate. If there
 is no issue, please file one before beginning to work on a PR. [Good first
 issues are labeled `E-easy`].
 
-## Discussion
-
-If you'd like to engage in a discussion outside of GitHub, you can [join
-Artichoke's public Discord server].
-
 ## Setup
 
 Boba includes Rust, Ruby, and Text sources. Developing on Boba requires
@@ -207,7 +202,6 @@ Regular dependency bumps are handled by [@dependabot].
   https://github.com/artichoke/boba/issues/new
 [good first issues are labeled `e-easy`]:
   https://github.com/artichoke/boba/labels/E-easy
-[join artichoke's public discord server]: https://discord.gg/QCe2tp2
 [rustup]: https://rustup.rs/
 [homebrew]: https://docs.brew.sh/Installation
 [bundler]: https://bundler.io/

README.md

@@ -2,7 +2,6 @@
 
 [![GitHub Actions](https://github.com/artichoke/boba/workflows/CI/badge.svg)](https://github.com/artichoke/boba/actions)
 [![Code Coverage](https://codecov.artichokeruby.org/boba/badges/flat.svg?nocache=2)](https://codecov.artichokeruby.org/boba/index.html)
-[![Discord](https://img.shields.io/discord/607683947496734760)](https://discord.gg/QCe2tp2)
 [![Twitter](https://img.shields.io/twitter/follow/artichokeruby?label=Follow&style=social)](https://twitter.com/artichokeruby)
 <br>
 [![Crate](https://img.shields.io/crates/v/boba.svg)](https://crates.io/crates/boba)