`__future__` imports allow dots before them

Bug report

Bug description:

__future__ imports don't check the amount of dots while checking from-import nodes for the module name, so they are still valid even if dots are put before the module name.

>>> from .__future__ import barry_as_FLUFL
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
    from .__future__ import barry_as_FLUFL
ImportError: attempted relative import with no known parent package
>>> 1 <> 2
True

Is this intended? Allowing dots before the module name seems improper considering __future__ is supposed to be part of the stdlib.

CPython versions tested on:

3.12, 3.13

Operating systems tested on:

Windows

Linked PRs