Replace TryStream to Stream

[ever0de]

While Stream<Item = Result<T, E>> implements TryStream<Ok = T, Error = E>,
https://docs.rs/futures/latest/futures/prelude/trait.TryStream.html#impl-TryStream-for-S

TryStream<Ok = T, Error = E> does not implement Stream<Item = Result<T, E>>.
That's why we were sometimes writing TryStream<Ok=T, Error = E, Item = Result<T, E>>.
Replace this with.

[coveralls]

Pull Request Test Coverage Report for Build 4210958655

• 5 of 5 (100.0%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 98.796%

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Totals
Change from base Build 4210253137:	0.0%
Covered Lines:	39723
Relevant Lines:	40207

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💛 - Coveralls

[panarch]

This is also nice improvement! Thanks a lot 👍