Docs update: `distillery.release` instead of `release`

[tomazzlender]

Summary of changes

A small fix in the docs. Use distillery.release instead of release.

Checklist

• [+] New functions have typespecs, changed functions were updated
• [+] Same for documentation, including moduledocs
• [+] Tests were added or updated to cover changes
• [+] Commits were squashed into a single coherent commit

Licensing/Copyright

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[tomazzlender]

I see now that there was already another PR that changed the docs, but was reverted.