Log Message:
py-project-metadata: updated to 0.8.0

0.8.0 (17-04-2024)

- Support specifying the ``metadata_version`` as 2.1, 2.2, or 2.3
- Always normalize extras following PEP 685
- Preserve the user-specified name style in the metadata. ``.canonical_name`` \ 
added to get the normalized name
- Require "version" in the dynamic table if unset (following PEP 621)
- Support extras using markers containing "or"
- Support empty extras
- Using ``.as_rfc822()`` no longer modifies the metadata object
- Fix email-author listing for names containing commas
- Separate core metadata keywords with commas, following the (modified) spec
- An error message reported ``project.license`` instead of ``project.readme``
- Produce slightly cleaner tracebacks
  Fix a typo in an exception message
- Subclasses now type check correctly
- The build backend is now ``flit-core``