semantic_version says pre-release versions can be higher than release versions

[jctanner]

Version
main

Describe the bug
semantic_version says "2.0.1-rc1" is greater than "1.0.1", which is perhaps true per the spec but I think we collectively think otherwise.

To Reproduce

versions = ['1.0.0', '2.0.0', '3.0.0-rc.1']
versions = [Version(x) for x in versions]
print(max(versions))

Expected behavior
Pre-release versions should only get marked as is_highest when no stable releases exist.

[mdellweg]

I did some experiment, and i cannot confirm the original claim that

"1.0.1-rc1" is greater than "1.0.1"

I can however see, that in case we have "2.0.0" and "3.0.0-rc.1" we do not want to consider the latter as the highest_(stable_)version. Can we not search the highest stable version and fall back to the highest of all if there was none?

In [1]: from semver import compare  # This is not what we are using. Just for comparison...

In [2]: from semantic_version import Version

In [3]: compare("1.2.3-rc", "1.2.2")
Out[3]: 1

In [4]: compare("1.2.3-rc", "1.2.3")
Out[4]: -1

In [5]: Version("1.2.3-rc") > Version("1.2.2")
Out[5]: True

In [6]: Version("1.2.3-rc") > Version("1.2.3")
Out[6]: False

In [7]: Version("1.2.3-rc.1") > Version("1.2.3")
Out[7]: False

In [8]: Version("1.2.3-rc.1") > Version("1.2.2")
Out[8]: True