Treat literal of all enum members equal to type itself

[JoniKauf]

Describe the bug
Treat Literal of all members of an enum the same way as the annotation of just that enum.

Code or Screenshots
https://discuss.python.org/t/treat-literal-of-all-elements-of-enum-equal-to-the-enum-in-type-annotations/108317
Here is the discuss.python.org link where i asked and showcased this issue. It seems to be a feature in most other type checkers already, with pyright being one of the exceptions.

Code re-pasted from there:

import enum
import typing as t

class Importance(enum.IntEnum):
    LOW = 1
    MEDIUM = 2
    HIGH = 3

type AllT = t.Literal[Importance.LOW, Importance.MEDIUM, Importance.HIGH]

class Task[T: Importance]:
    ...

def manage_task(task: Task[AllT]) -> t.Any:
    ...

task: Task[Importance] = ...

manage_task(task)  # error

[tapetersen]

The test in the conformance suite didn't check both directions of the equivalency python/typing#2323

That has been corrected with a very simple test-case that pyright now fails in github.com/python/typing/pull/2324