[kotlin] better oneOf, anyOf support

[wing328]

better oneOf, anyOf support via the option generateOneOfAnyOfWrappers

with this option enabled, oneOf, anyOf schemas will be generated as wrapper/container similar to the Java client implementation of oneOf, anyOf.

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[wing328]

cc
@jimschubert (2017/09) ❤️, @dr4ke616 (2018/08) @karismann (2019/03) @Zomzog (2019/04) @andrewemery (2019/10) @4brunu (2019/11) @yutaka0m (2020/03) @stefankoppier (2022/06)

[DearDhruv]

is anyOf still valid?
It seems I am having issues with for generating below openapi schema for kotlin.

            required:
                - type
                - modules
            type: object
            allOf:
                - "$ref": "#/components/schemas/PageBase"
            properties:
                type:
                    type: string
                modules:
                    type: array
                    minItems: 1
                    items:
                        anyOf:
                            - "$ref": "#/components/schemas/Xyle"
                            - "$ref": "#/components/schemas/XyModule"
                            - "$ref": "#/components/schemas/XyTextModule"
                            - "$ref": "#/components/schemas/Xyarousel"
                            - "$ref": "#/components/schemas/Xydule"
                            - "$ref": "#/components/schemas/Xye"
                            - "$ref": "#/components/schemas/XyearchModule"
                            - "$ref": "#/components/schemas/XyesModule"
                            - "$ref": "#/components/schemas/XyileModule"
                            - "$ref": "#/components/schemas/XyinesModule"
                            - "$ref": "#/components/schemas/XynModule"
                            - "$ref": "#/components/schemas/Xyodule"
                            - "$ref": "#/components/schemas/XyontentModule"
                            - "$ref": "#/components/schemas/XypModule"
                            - "$ref": "#/components/schemas/XyroductsCarousel"
                            - "$ref": "#/components/schemas/Xyule"
            discriminator:
                propertyName: type
                

I get the class name alright but the import as import xx.yy.openapi.model.AnyOfLessThanXyleGreaterThan
and property as @SerializedName("modules") val modules: kotlin.collections.List<AnyOfLessThanXyleGreaterThan>,

The literal text is LessThan and GreaterThan instead of < , >

I am using id("org.openapi.generator") version "7.10.0"