0.8.0

What's Changed

• fix!: use correct representation of Coding object in mappings by @korikuzma in #457
• fix!: xrefs should have exactMatch for ConceptMapping.relation by @korikuzma in #460
• fix: resolve pydantic serializer warnings in _add_merged_meta by @korikuzma in #461

Full Changelog: 0.7.1...0.8.0