Testing ASP.NET Core with trimming

### Is there an existing issue for this?

- [X] I have searched the existing issues

### Is your feature request related to a problem? Please describe the problem.

We're annotating ASP.NET Core for trimming in .NET 7. In theory, the linker and trim warnings should ensure frameworks, libraries and apps work.

We should double-check that ASP.NET Core continues to run in some trimmed, published apps.

### Describe the solution you'd like

With trimming it's difficult to test trimmed features in isolation, e.g. an app uses features A and B. Did A and B only work because they were both used, etc. Building and running an app to test each feature in isolation isn't realistic.

We should do some basic smoke testing of core scenarios.

e.g.
MVC
Minimal API
SignalR
AuthN/AuthZ
Kestrel/IIS/HttpSys
Data protection/security/identity

### Additional context

_No response_