set schema name for EnumTypes

[sam0r040]

At Springwolf we use the parsed schemas to generate Examples. Thereby we use the field Schema.getName() for all schemas including enums.

When enumAsRef is used, the name of the enum is missing in its class schema. Also, when serialized, the name of a schema is ignored because of the @JsonIgnore annotation.

This PR adds the schema name for enums. We found the following comment:

swagger-core/modules/swagger-core/src/main/java/io/swagger/v3/core/jackson/ModelResolver.java

Line 379 in 5ee9cef

// Store off the ref and add the enum as a top-level model

And therefore believe that all enum classes should appear as models, resulting in the adaption of the tests.

Relates to #4722

[micryc]

Hi @sam0r040 could you share some details on how you used enumAsRef annotation ? I think it should work as intended