v0.6.4

Changelog

• 13a78eb Avoid unnecessary type conversions (#222)
• 452f1fe Fix #130 in a backward-compatible way (#219)
• ae67bb4 Force Draft version of JsonSchema (#221)
• 2e50b79 Update Go and Goreleaser to 1.20, update dependencies (#231)
• 817f5b4 Update Golang to 1.21.4
• f0a7d52 Update Readme.md
• b7d7b4d Update Readme.md (#232)
• 278385f Update Readme.md to add fullgroup explanation (#220)
• 71fd5f8 fix: add missing output formats in error message (#213)
• 6ae8c45 openapi2jsonschema.py now correctly fails if no FILE is passed (#244)