LooseVersion deprecated

The LooseVersion module has been deprecated:

  /builds/pub/terrareg/terrareg/models.py:2985: DeprecationWarning: distutils Version classes are deprecated. Use packaging.version instead.
    key=lambda x: LooseVersion(x.version),

The replacement packaging.version.Version does not support arbitrary suffixes:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "terrareg/venv/lib/python3.8/site-packages/packaging/version.py", line 266, in __init__
    raise InvalidVersion(f"Invalid version: '{version}'")
packaging.version.InvalidVersion: Invalid version: '5.2.1-as'

We can create a custom implementation that allows arbitrary beta suffixes.