[scala][client]: scala-http4s: minor improvement (enum companion method, remove implicit, error handling)

[JennyLeahy]

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[JennyLeahy]

Please review

@clasnake @shijinkui @ramzimaalej @chameleon82 @Bouillie @Fish86

[wing328]

thanks again for the PR and took my feedback

from what I know, there's no breaking change in this PR so I'll merge it later this week

thanks for the contribution.

[wing328]

when you're free next week, can you please PM me to discuss the breaking change? thanks

i think i may find a way to incorporate it in the upcoming minor release (which allows breaking changes with fallback)

https://join.slack.com/t/openapi-generator/shared_invite/zt-12jxxd7p2-XUeQM~4pzsU9x~eGLQqX2g

[JennyLeahy]

@wing328 sorry, I missed the invitation. Could you send me the invite again? Thanks a lot

[wing328]

please join via https://join.slack.com/t/openapi-generator/shared_invite/zt-2uoef5v0g-XGwo8~2oJ3EoziDSO1CmdQ