dev: Nicer error from MW if the DB doesn't exist
Prior to this change if a DB did not exist you would get some unhelpful postgres error.
Now you get an actual error saying we can't find the DB anywhere.
Bug: T288442
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Prior to this change if a DB did not exist you would get some unhelpful postgres error.
Now you get an actual error saying we can't find the DB anywhere.
Bug: T288442