Stop gzipping zuul status json in zuul

It is expensive for zuul to do gzipping of data in zuul. Stop gzipping
here and have apache (or some other proxy) do it for you in cases where
smaller json is helpful. This offloads the work from zuul so that it can
focus on scheduling tests.

partial-bug: 1326170
Change-Id: Ieef0a19b4b36b28118a6a93ebd595a5287848034
Merge "Stop gzipping zuul status json in zuul"