[BUG] Missing value/name mapping for shared enum definition

Description

If a type is defined as a shared enum in the open api specification and the values are not upper case only, the generated code will not deserialize/serialize the enum value properly.
If the type is defined as an inline enum type, the generated code is correct and serialization/deserialization works.

openapi-generator version

5.3.0, jaxrs-resteasy

OpenAPI declaration file content or url

Example snippet from .yaml definition:

...
TermOfPaymentEnum:
          type: string
          enum:
            - zero
            - ten
            - fifteen
...

Steps to reproduce

1. Define a enum type with lower case values in components/schemas
2. Generate the code with jaxrs-resteasy generator

The generated code is:

public enum TermOfPaymentEnum {
    ZERO, TEN, FIFTEEN
}

Notice that the generated enum has no value attribute and no fromValue and toString() implementations.
I would expect the following code:

public enum TermOfPaymentEnum {
  ZERO("zero"),

  TEN("ten"),

  FIFTEEN("fifteen"),


  private String value;

  TermOfPaymentEnum(final String value) {
    this.value = value;
  }

  @Override
  @JsonValue
  public String toString() {
    return String.valueOf(value);
  }
}

Related issues/PRs

REQ 8084

Start with the jaxrs-resteasy generator and compare generated code for the shared enum and inline enum cases described in the issue. Verify that lower-case OpenAPI values are preserved during serialization and deserialization, then add or run a regression test covering TermOfPaymentEnum-like values and confirm the generated enum includes the expected mapping behavior.