'MkSolo sometimes printed incorrectly in diagnostics
## Summary
In some error messages GHC prints `'Solo a` instead of `'MkSolo a`
## Steps to reproduce
```haskell
{-# LANGUAGE DataKinds #-}
module T where
import Data.Proxy
import Data.Tuple
p :: Proxy ('MkSolo Int)
p = Proxy :: Proxy Int
```
This code will output
```
T.hs:9:5: error: [GHC-83865]
• Couldn't match type 'Int' with ''Solo Int'
Expected: Proxy ('Solo Int)
Actual: Proxy Int
• In the expression: Proxy :: Proxy Int
In an equation for 'p': p = Proxy :: Proxy Int
|
9 | p = Proxy :: Proxy Int
| ^^^^^^^^^^^^^^^^^^
```
## Expected behavior
`'MkSolo` should be printed instead of `'Solo`
## Environment
* GHC version used:
master branch
issue