Log Message:
py-tox: updated to 4.21.2

v4.21.2 (2024-10-03)
Bugfixes - 4.21.2
Include tox.toml in sdist archives to fix test failures resulting from its lack.

v4.21.1 (2024-10-02)
Bugfixes - 4.21.1
Fix error when using requires within a TOML configuration file
Fix error when using deps within a TOML configuration file
Multiple fixes for the TOML configuration by @gaborbernat.:
Do not fail when there is an empty command within commands.
Allow references for set_env by accepting list of dictionaries for it.
Do not try to be smart about reference unrolling, instead allow the user to \ 
control it via the extend flag, available both for posargs and ref replacements.
The ref replacements raw key has been renamed to of.

v4.21.0 (2024-09-30)
Features - 4.21.0
Native TOML configuration support
Improved Documentation - 4.21.0
Update Loader docs