message: add aspell-en to fedora instructions
  I had to install it in fedora 30 for the git hooks to work.
diff: @@ -40,7 +40,7 @@ for how to update or override dependencies.
  On Fedora (maybe also other red hat distros), run the following:
  ```
  - dnf install cmake libtool libstdc++ ninja-build lld patch
  + dnf install cmake libtool libstdc++ ninja-build lld patch aspell-en
  ```
  On macOS, you'll need to install several dependencies. This can be accomplished via [Homebrew](https://brew.sh/):
  