[services] Rename Reactor Utility
Summary:
https://linear.app/comm/issue/ENG-1086/discuss-the-structure-of-reactor-utility
Renaming ReactorUtility -> ReactorStatusHolder
Test Plan:
services should still build
cd services yarn test-blob-service yarn test-backup-service
Reviewers: ashoat
Reviewed By: ashoat
Subscribers: ashoat, palys-swm, Adrian, atul, yayabosh
Differential Revision: https://phabricator.ashoat.com/D3931