Summary:
This change makes all instrumentation tests to be executed in sequence in independent retriable processes.
With a new test being open sourced recently our CI stability degraded.
This PR should bring back stability because tests won't affect each other and will have shorter lifetime
Closes https://github.com/facebook/react-native/pull/7353
Differential Revision: D3259081
fb-gh-sync-id: 48ccdb5dbd561d416526497ff474378db9ca3c60
fbshipit-source-id: 48ccdb5dbd561d416526497ff474378db9ca3c60
Konstantin Raev