Following T214557, T245547, T245817, T245830, and T245831 all Wikibase code operates in the "entity source based federation" mode any way, hence the conditional logic is redundant.
- Update WikibaseClient:
- Update WikibaseRepo: https://gerrit.wikimedia.org/r/#/c/mediawiki/extensions/Wikibase/+/574074
- Remove DataAccessSettings::useEntitySourceBasedFederation: