Make enums as sealed classes generate sealed interfaces#5921

BoD merged 2 commits intojava-enum-as-class-non-null-raw-valueapollographql/apollo-kotlin:java-enum-as-class-non-null-raw-valuefrom

rework-enum-sealed-classesapollographql/apollo-kotlin:rework-enum-sealed-classesCopy head branch name to clipboard