Fix Unversioned Endpoints

[commonsensesoftware]

Fix Unversioned Endpoints

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Description

Fixes the routing of unversioned endpoints. The ApiVersioningMatcherPolicy builds edges and a jump table based on versioned endpoints. An Endpoint is versioned if it has ApiVersionMetadata applied. The IEndpointSelectorPolicy.AppliesToEndpoints builds and enforces versioning policies when any Endpoint is versioned in a provided set. Before this change, it was possible that a versioned Endpoint could provide a route template with a fallback that would also include overlapping unversioned endpoints in the same set. As a result, any unversioned endpoints have versioning policies enforced and become unrouteable.

This change ensures that unversioned endpoints remain routeable without any versioning policies. If an endpoint really doesn't exist, 404 is still the final destination.