add bug test case dexie indexed db with findOne subscription + exec

[willhoney7]

This PR contains:

• a bug test case

Describe the problem you have without this PR

Using dexie (with fake-indexedDb on node or in the browser with real indexedDb), if you subscribe to a certain type of query, then delete the value, then execute the query, it will still return a result. (see the test)

Some notes:

• this bug does not replicate in memory storage. It may replicate with other storages, but I did not test.
• I think the findOne part is relevant but not 100% sure.
• It is relevant that the query I show does not have a "selector" field. If you update the query to have a selector, the bug will not occur.
• eventReduce on/off does not matter

Sorry the test is a little goofy. I had a hard time getting the env to work correctly and also I can't get the assertion to work correctly? It may be waiting on some async work I'm not flushing/handling. But it throws an error and clearly shows there's a bug.