expression has type "Literal[-1]", variable has type "Literal[-1]"

```python
from typing import Literal

x: Literal[-True] = -1
```

results in

```
main.py:3: error: Incompatible types in assignment (expression has type "Literal[-1]", variable has type "Literal[-1]")  [assignment]
```

https://mypy-play.net/?mypy=latest&python=3.10&gist=3e6413c5ba1b82c11ff2ae6b66abd03e

Instead mypy should reject the type declaration.