message: remove CI badge
diff: # Miri
  -[![Actions build status][actions-badge]][actions-url]
  -
  -[actions-badge]: https://github.com/rust-lang/miri/workflows/CI/badge.svg?branch=master
  -[actions-url]: https://github.com/rust-lang/miri/actions
  -
  An experimental interpreter for [Rust][rust]'s
  [mid-level intermediate representation][mir] (MIR). It can run binaries and
  test suites of cargo projects and detect certain classes of
  