OutputChunked don't need to do twice super.flush()

[jackjoesh]

Describe the bug

I think the OutputChunked don't need to do twice super.flush(), it may waste cpu usage

can we modify the code, as following:

Wait for help, thank you!

[theigl]

@jackjoesh: Thanks for your suggestion. Please provide a PR with your suggested changes so we can discuss it further and can see what issues it might cause.

[jackjoesh]

@jackjoesh: Thanks for your suggestion. Please provide a PR with your suggested changes so we can discuss it further and can see what issues it might cause.

Thank you, here is my pr: #839
Please check it.