Unify ZoneInfo.from_file signature

[hrimov]

Bug report

Bug description:

While enhancing stubs for ZoneInfo.from_file in typeshed, I noticed that the regression in the from_file signature was caused by the argument clinic migration, but without specifying an argument alias - intentionally or not, I don't know.

Therefore, I believe it would be a good approach to unify both signatures for the native and Python versions of zoneinfo. Since AC takes priority and fobj is a pos-only argument, I think the more appropriate approach would be to update Python's fallback.

CPython versions tested on:

CPython main branch

Operating systems tested on:

macOS

Linked PRs

• gh-135273: Unify ZoneInfo.from_file signatures #135274