[bug] Integer enum support

[xiaoxiangmoe]

I found we response enum in VO as string enum. Is there any approach to response int enum?

related issue: springdoc/springdoc-openapi#709

[T3rm1]

Here is a PR that fixes it: #4769
But it looks like the project is dead. There is barely any activity any more and @frantuma is the only rarely active member of this project.