Fix MiskKotlin OpenApiGenerator types

[andrewwilsonnew]

Found a couple of bugs (so can we include this in the branch release)

• void return from Action should be Response<Void>
• Array type should be List in Misk

@guiarn , @wing328

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@guiarn @wing328

[sleiyer]

I don't have a lot of context of this file

But with the change above from Array -> List https://github.com/OpenAPITools/openapi-generator/pull/21390/files#diff-4c93f665fc6f95375f506f04f625f2cd823f4bf4907425b607124ba893812f73R1

Should this be kotlin.List<Pet> instead

[andrewwilsonnew]

Was late last night. Nice, fixed to kotlin.collections.List

[andrewwilsonnew]

@wing328 any chance we could get this into the 7.14.0 branch?