Fix cargo fmt error

It's a rookie mistake and you hate to see it

eth2/attester/src/lib.rs

@@ -119,8 +119,7 @@ impl<T: SlotClock, U: BeaconNode, V: DutiesReader, W: Signer> Attester<T, U, V,
             validator_index,
         };
 
-        self.beacon_node
+        self.beacon_node.publish_attestation(free_attestation)?;
-            .publish_attestation(free_attestation)?;
         Ok(PollOutcome::AttestationProduced(slot))
     }