docs: remove fuzzit badge (#3719)

The badge no longer displays. I believe this is due to the acquisition by GitLab; other repositories seem to be reporting similar issues.

cranelift/README.md

@@ -9,7 +9,6 @@ into executable machine code.
 
 [BA]: https://bytecodealliance.org/
 [![Build Status](https://github.com/bytecodealliance/wasmtime/workflows/CI/badge.svg)](https://github.com/bytecodealliance/wasmtime/actions)
-[![Fuzzit Status](https://app.fuzzit.dev/badge?org_id=bytecodealliance)](https://app.fuzzit.dev/orgs/bytecodealliance/dashboard)
 [![Chat](https://img.shields.io/badge/chat-zulip-brightgreen.svg)](https://bytecodealliance.zulipchat.com/#narrow/stream/217117-cranelift/topic/general)
 ![Minimum rustc 1.37](https://img.shields.io/badge/rustc-1.37+-green.svg)
 [![Documentation Status](https://docs.rs/cranelift/badge.svg)](https://docs.rs/cranelift)