[BUG][TYPESCRIPT] Non-nullable type is generated as nullable

[FrenchGithubUser]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
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Description

This interface is generated:

export interface TitleGroupHierarchyLite {
    'affiliated_artists': Array<AffiliatedArtistLite>;
    'category'?: TitleGroupCategory | null;
    'content_type': ContentType | null;
    'covers': Array<string>;
    'edition_groups': Array<EditionGroupHierarchyLite>;
    'id': number;
    'name': string;
    'original_release_date': string | null;
    'original_release_date_only_year_known': boolean;
    'platform'?: Platform | null;
    'series'?: SeriesLite | null;
    'tags': Array<string>;
}

but content_type should not be nullable (according to the openapi spec)

openapi-generator version

I tried with latest and it gives the same bug

OpenAPI declaration file content or url

https://pastebin.com/K1QVzVDK

Generation Details

npx openapi-generator-cli generate -g typescript-axios -i http://127.0.0.1:8080/swagger-json/openapi.json   -o ./src/services/api-schema -t .openapi-generator/templates --config .openapi-generator/openapi-generator.config.json --global-property=apiDocs=false,modelDocs=false,skipFormModel=false

mustache template: https://github.com/Arcadia-Solutions/arcadia/blob/main/frontend/.openapi-generator/templates/api.mustache

Steps to reproduce

generate the api.ts file with the provided command, template and openapi json schema.

Related issues/PRs

None found

Suggest a fix

No idea :/