Determine behavior for GeneratedComClass on a type with no GeneratedComInterface interfaces

[jkoritzinsky]

Do we want to warn / bail if there are no interfaces with GeneratedComInterface on a GeneratedComClass type?

Originally posted by @elinor-fung in #83755 (comment)

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Issue Details

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Do we want to warn / bail if there are no interfaces with GeneratedComInterface on a GeneratedComClass type?

Originally posted by @elinor-fung in #83755 (comment)

Author:	jkoritzinsky
Assignees:	-
Labels:	area-System.Runtime.InteropServices, untriaged
Milestone:	-

[AaronRobinsonMSFT]

Since the primary focus for the COM source generator in .NET 8 is for our first party teams, we can go with the yes and then relax it in the future if needed.

[jkoritzinsky]

Completed with #87436