Reserved words mappings don't work with enums

[Colman]

Describe the bug
When generating an enum that has a value that is a reserved word, the --reserved-words-mappings param is ignored

Expected behavior
The --reserved-words-mappings param should not be ignored for enum values

To Reproduce

{
  "openapi": "3.0.1",
  "info": {
    "title": "Rental v2",
    "description": "Rental related info",
    "version": "v2"
  },
  "paths": {},
  "components": {
    "schemas": {
      "EFoo": {
        "enum": [
          "Late"
        ],
        "type": "string"
      }
    },
    "securitySchemes": {}
  },
  "tags": []
}

Run:

java -cp 'openapi-generator-cli-5.2.1.jar;openapi-dart-generator-5.12.jar' org.openapitools.codegen.OpenAPIGenerator generate -g dart2-api --reserved-words-mappings late=late

Produces the following enum in Dart:

enum EFoo { late_ }

The expected enum in Dart is:

enum EFoo { late }

Versions
openapi-dart-generator-5.12.jar
I believe it still happens in 8.1 since the code still contains the suspected cause

Suspected cause
The toEnumVarName function calls the escapeReservedWord function before calling the toVarName function. This causes the var name to not be found in the reserved words mappings.

Workaround
Use --reserved-words-mappings Late=,Late_=late

[rvowles]

Looking at the way this is handled, its actually handed to the Dart generator by the base infrastructure. The AbstractDartCodegen class (which comes from the main project) is what loads these in and the reserved words are predefined there. It looks like late is built in. Perhaps re-log your issue on the main OpenAPIGenerator - feel free to link this ticket as well as I would like to know what they say about it.