Create a doc about using the cookie APIs in ASP.NET Core

ASP.NET Core includes a number of API areas for working with cookies. The APIs go beyond the simple "get and set cookies" for the request and response and include new APIs for controlling the various policy options around cookies (see [Microsoft.AspNetCore.CookiePolicy](https://github.com/aspnet/Security/tree/dev/src/Microsoft.AspNetCore.CookiePolicy)).

The doc should also detail the default options and policy applied to the various cookies the framework itself issues. I'd likely place it in the "Fundamentals" section, with potential cross-reference from the "Security" section.

@Tratcher

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[Associated WorkItem - 67057](https://dev.azure.com/msft-skilling/Content/_workitems/edit/67057)