Rollup merge of #136630 - jieyouxu:render_tests, r=ChrisDenton

Change two std process tests to not output to std{out,err}, and fix test suite stat reset in bootstrap CI test rendering

I don't really know how to test if this unbreaks CI (since #136607 reported that this breaks the CI test rendering *sometimes*).

Fixes #136607.

r? `@ChrisDenton` (two Windows process tests, but feel free to reroll)