Lexicon v3.5.4

Changed

• Support both tldextract 2.x and 3.x
• Upgrade third-party dependencies
• Validate PowerDNS provider parameters (#755)
• Support dnspython>=2.1 for localzone provider (#760)
• Update Mythic Beasts documentation (#693)
• Fix documentation build and publication

Deleted

• Remove mock and nose dependencies (#706)