When implementing AsyncNodeGraphType ExecutionStrategy throws InvalidOperationException

I found that when implementing `AsyncNodeGraphType` the `ExecutionStrategy` class will throw an `InvalidOperationException` since the following call returns null:
https://github.com/graphql-dotnet/graphql-dotnet/blob/ed720f46e26704ed457b723801637d9d726f45bd/src/GraphQL/Execution/ExecutionStrategy.cs#L636

The problem seems to be that the execution strategy is not awaiting the result and is trying to find the GraphType of Task instead of just T.

Our implementation broke after we upgraded GraphQL, here you can see the version of our packages:
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Hope this gives you enough information to fix it