[BUG][C++][C++ Rest SDK] Enum types with '-' character in name don't get escaped

[stkrwork]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
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Description

    enumTestType:
      type: string
      enum: [test-type-1, test-type-2]
      example: test-type-1

This will produce invalid enum value names. Example:

    enum class eEnumTestType
    {
        EnumTestType_test-type-1,
        EnumTestType_test-type-2,
    };

Result should be:

    enum class eEnumTestType
    {
        EnumTestType_test_type_1,
        EnumTestType_test_type_2,
    };

or:

    enum class eEnumTestType
    {
        EnumTestType_testtype1,
        EnumTestType_testtype2,
    };

openapi-generator version

Release 4.1.2

Suggest a fix

Remove the character or replace it with '_'.