remove eagerError (#2524)

Wait all futures complete before return when there are errors in `batch backfiller`
diff --git a/app_dart/lib/src/request_handlers/scheduler/batch_backfiller.dart b/app_dart/lib/src/request_handlers/scheduler/batch_backfiller.dart
index 792639e..932b823 100644
--- a/app_dart/lib/src/request_handlers/scheduler/batch_backfiller.dart
+++ b/app_dart/lib/src/request_handlers/scheduler/batch_backfiller.dart
@@ -92,7 +92,7 @@
       });
       // Schedule all builds asynchronously.
       // Schedule after db updates to avoid duplicate scheduling when db update fails.
-      await Future.wait<void>(backfillRequestList(backfill), eagerError: true);
+      await Future.wait<void>(backfillRequestList(backfill));
     } catch (error) {
       log.severe('Failed to update tasks when backfilling: $error');
     }