We need to fetch all committed transaction entries from config.transaction tables, with lastWriteOpTime.ts <= startApplyingDonorTimestamp, before applying donor oplog entries. Currently, we have createCommittedTransactionsPipelineForTenantMigrations() which is used by multi-tenant migration protocol to fetch committed transaction entries only for a given tenant id. We don't need such a complex pipeline for shard merge protocol as we are migrating all tenants from donor. So, simple find command should be suffice for shard merge.