fix: Don't try to fetch table metadata when updating query schema

[sean-rose]

Description

A change made in #8486 is resulting in the dryrun cloud function always trying to fetch table metadata when updating query schemas, but during deploys to stage the tables don't exist, so deploying ETLs without schema.yaml files to stage is now consistently failing (e.g. the events_stream_v1 ETLs, which is blocking #8596).

As a quick fix this undoes the problematic change, though that might break some of the caching speed improvements implemented in #8486 (cc @scholtzan).

An alternate solution could be to update the dryrun cloud function to either not try to fetch the table metadata when a query is being passed in, or not fail the entire function call due to a table metadata fetch error if a query is being passed in.

Related Tickets & Documents

• Dryrun caching #8486
• feat(events_stream): Add document_event_number column to events_stream_v1 tables and event_id column to events_stream views (DENG-9800) #8596

Reviewer, please follow this checklist

[sean-rose]

I've confirmed this fix works by temporarily applying it in #8596, and the corresponding deploy-changes-to-stage CI job succeeded.