Update Web API Tutorials to Minimal APIs (Epic tracker)

In the Tutorials section of the ASP.NET Core docs, there are currently 6 tutorials, 5 of which create a controllers-based app and only one creates a Minimal API app.

These tutorials should be updated so that all or nearly all of them demonstrate the target feature in a Minimal API app.

Specifically, the "Create a controller-based web API with ASP.NET Core" can remain but the other four Tutorials in the "Controller-based APIs" section should be converted to use Minimal APIs.

In addition, the "Controller-based APIs" and "Minimal APIs" sections should be dropped so that all tutorials just appear under "APIs", and the single controller-based tutorial should appear last in the list.

[The following was added by wadepickett]
Related to: #35742

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[Associated WorkItem - 544746](https://dev.azure.com/msft-skilling/Content/_workitems/edit/544746)