SharedDbConnectionScope Connection is null when the asynchronous call is finished

[kccarter76]

Describe the bug
null exception is triggered on the SharedDbConnection scope while asynchronously streaming data from a LoadAsync. this typically is fired at the end of the iterator when it goes to close the connection.

To Reproduce
Steps to reproduce the behavior:

            await foreach (Models.Person person in people.AsAsyncEnumerable().LoadAsync())
            {
                foreach (Models.Renter renter in person.Renters)
                {
                    Context.Renters.Delete(renter);
                }

                Context.People.Delete(person);
            }

Expected behavior
I expect the connection object to not be null, so it can closed and disposed of correctly.

Screenshots
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Desktop (please complete the following information):

• OS: Windows
• Version .NetStandard 2.1

Additional context
Add any other context about the problem here.

[kccarter76]

since enhancing the shared db connection to track all asynchronous threads and the number of times each thread adds a shared connection to the heap. this issue has not occurred in multiple test runs.