Versioning through custom headers no longer working after v14 upgrade

[jfoley96]

Hello,
We have been using the API "Versioning through custom headers" principle, wherein nswag was generating {version} placeholder and we replaced the value based on incoming client request header value. This {version} placeholder is not available anymore after upgrading to the latest version of NSwag.

Startup.cs implementation:

` services
.AddControllers(options =>
{
options.UseGeneralRoutePrefix("api/v{version:apiVersion}");
options.EnableEndpointRouting = true;
options.Filters.Add();
})
.AddNewtonsoftJson();

        services.AddRouting(options => options.LowercaseUrls = true);

        services.AddApiVersioning(options =>
        {
            options.ReportApiVersions = true;
            options.AssumeDefaultVersionWhenUnspecified = true;
            options.DefaultApiVersion = new ApiVersion(1, 0);
        });

        services.AddInfrastructure(Configuration);

        // Register the Swagger generator, defining 1 or more Swagger documents
        services.AddOpenApiDocument(document =>
        {
            document.DocumentName = "v1";
            document.Title = "xxxxxx Web APIs";
            document.Version = "1.0";
      
            // This adds the ability to handle a custom required header in the OpenAPI contract
            document.OperationProcessors.Add(new OperationRequiredHeaderAttributes());
        });

Generated code (missing the version number in the url) :
// Operation Path: "api/v{version}/security/groups" urlBuilder_.Append("api/v"); urlBuilder_.Append("/security/groups");
`