fix: useEventBus by propagating config to DefaultEventsService

This setting was added by reading from an optional `config` argument.
This was never passed, so `auto` was always assumed.
https://github.com/backstage/backstage/pull/27227/files#diff-cffd40a187b4fc584f03c968517fbacc110bde6a467f2384bbd92b803d3db47eR374-R379

Signed-off-by: RedlineTriad <39059512+RedlineTriad@users.noreply.github.com>

packages/backend-legacy/src/index.ts

@@ -73,9 +73,10 @@ function makeCreateEnv(config: Config) {
     discovery,
   });
 
-  const eventsService = DefaultEventsService.create({ logger: root });
+  const eventsService = DefaultEventsService.create({ logger: root, config });
   const eventBroker = new DefaultEventBroker(
     root.child({ type: 'plugin' }),
+    config,
     eventsService,
   );
   const signalsService = DefaultSignalsService.create({