docs: remove nix-shell section from contributing.md (#1453)

Author: Zaechus

CONTRIBUTING.md

@@ -20,32 +20,3 @@
 - Take part in troubleshooting and testing
 - Star the repo
 - Follow the maintainers
-
-## Development with nix
-
-When you develop with nix you can use the [dev shell](https://github.com/pystardust/ani-cli#nix-shell).
-
-To run the dev shell you can run the following command in the repository root:
-```shell
-nix-shell
-```
-
-The dev shell includes the following packages:
-- runtime dependencies of ani-cli
-- shfmt
-- shellcheck
-
-Its also possible to use alternative packages for the video player or add features with this command:
-```shell
-nix-shell --arg <feature> true
-```
-These are the packages available in the dev shell:
-- `withVlc`
-- `withIina`
-- `chromecastSupport`
-- `syncSupport`
-
-Just chain these commands together when you wanna multiple features for example:
-```shell
-nix-shell --arg withVlc true --arg chromecastSupport true
-```