[risk=no] Use --runInBand to mitigate jest timeouts (#1726)
[risk=no] Use --runInBand to mitigate jest timeouts (#1726)

Stolen from @zarsky-broad and split out ahead of https://github.com/all-of-us/workbench/pull/1723 to mitigate high flakiness we're seeing.

https://jestjs.io/docs/en/troubleshooting#tests-are-extremely-slow-on-docker-and-or-continuous-integration-ci-server
all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench,all-of-us/workbench