BUG: DataFrame.insert value is too strict

[phofl]

Describe the bug
A clear and concise description of what the bug is.

To Reproduce

1. Provide a minimal runnable pandas example that is not properly checked by the stubs.
2. Indicate which type checker you are using (mypy or pyright).
3. Show the error message received from that type checker while checking your example.

df = DataFrame({"a": [1, 2]})
df.insert(loc=0, column="b", value=None)

error: Value of type variable "ListLike" of "insert" of "DataFrame" cannot be "None"  [type-var]

Please complete the following information:

• OS: [e.g. Windows, Linux, MacOS] MacOS
• OS Version [e.g. 22] Venturar 13.1
• python version 3.10
• version of type checker mypy 0.991
• version of installed pandas-stubs latest

Additional context
Add any other context about the problem here.

According to the main repo, any Scalar is allowed

[Dr-Irv]

Need to change

pandas-stubs/pandas-stubs/core/frame.pyi

Line 546 in 495e91f

value: int | ListLike,

to be value: Scalar | ListLikeU | None with appropriate tests.