bug: Specifier("==1.0.*") does not contain Version("1a1")

[mayeut]

This bug was initially reported in #425
In this specific instance, the meaning of the specifier is clear whereas it is not the case in the original description of #425.
This led me to open a specific issue for this one.

>>> from packaging import __version__
>>> print(__version__)
21.4.dev0
>>> from packaging.specifiers import Specifier
>>> from packaging.version import Version
>>> spec = Specifier("==1.0.*")
>>> version1 = Version("1a1")
>>> version2 = Version("1.0a1")
>>> version1 == version2
True
>>> spec.contains(version1, prereleases=True) == spec.contains(version2, prereleases=True)
False

[pfmoore]

I think this is another aspect of the same issue:

>>> Specifier(">=3.11").contains("3.11.0rc1", True)
False

It seems to me that if I ask for prereleases, I'd want 3.11.0rc1 to be considered as >=3.11. Although I'd happily concede that PEP 440 seems unclear on this.