[java] Apply additionalModelTypeAnnotations on enums

[agilob]

Fixes #6055

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[agilob]

circleci is failing as it finds new changes after generation, but all changes are whitespace

[alimac87]

@agilob, just a thought: in enumClass.mustache and enumOuterClass.mustache could you remove the newline between the end of comment "*/"
and "{{>additionalModelTypeAnnotations}}" to avoid the whitespace changes (and blank lines) in generated files?

e.g. in https://github.com/OpenAPITools/openapi-generator/pull/7539/files#diff-758d6dce1a3e4c52e3e30bff17da160f line 3 would read:
*/{{>additionalModelTypeAnnotations}}

[agilob]

This time I'm going to take readability of mustache files over extra whitespace in generated code (which you shouldnt modify anyway?)

With your changes it looks even worse :P

[alimac87]

Yep fair point - I thought I'd tested this and seen the generated code include a new line between the "*/" and "@", but I must have been mistaken.

Edit: this was the version which did not include the empty lines in output:
{{>additionalModelTypeAnnotations}}public enum

[UnleashSpirit]

Is there no potential side effect adding annotation targeted for classes on enums ?
I often use

@lombok.Builder
@lombok.NoArgsConstructor
@lombok.AllArgsConstructor

But on enums, strange no ?
The @lombok.Builder will end iwth "Cannot instantiate the type EnumCategorie"
As it's additionalModelTypeAnnotations I'm not sure this is a good idea