Remove virtual local cache entries

Why is this change being made?

Local upstreams for virtual repositories are out of scope for the MVP,
so drop the *_virtual_local_cache_entries tables and related "local or remote" upstream wording from the schema doc to keep it focused on the
first iteration.

Addressed !19225 (comment 3249312903)

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Commits

• Remove virtual local cache entries

Local upstreams for virtual repositories are out of scope for the MVP, so drop the *_virtual_local_cache_entries tables and related "local or remote" upstream wording from the schema doc to keep it focused on the first iteration.

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