Formatter drops unboxed tuples hashes

The formatter will reformat unboxed tuples to regular tuples by dropping the `#` character and removing necessary whitespace between the unboxed tuple and tuples elements. For example, the following type:

```haskell
import GHC.Exts (State#, RealWorld)

newtype T a = T { unT# :: State# RealWorld -> (# State# RealWorld, a #) }
```

would be reformatted as:

```haskell
newtype T a
= T { unT# :: State# RealWorld -> (State# RealWorld, a) }
```

I'm not sure if this is specific to certain configuration. The formatter will drop unboxed tuples even if:

- The `.stylish-haskell.yaml` option has `cabal: false` and `UnboxedTuples` listed under `language_extensions:`.
- The `UnboxedTuples` extension is listed under `default-extensions` in the package cabal file.
- A `{-# LANGUAGE UnboxedTuples #-}` pragma is added to the `*.hs` file containing the type `T`.