staging: Dedicate an indexer worker
The end goal is to replicate our current production environment. And making sure writing to the journal with more than 1 indexer behave properly.
Related to T2780
Test Plan
bin/octocatalog:
- worker0 -> wants to drop the indexer configuration part (ok)
- worker3 -> wants to add the indexers' configuration (well in theory, i've got no fact on it)
Migrated from D5056 (view on Phabricator)