Updated to comply with new clippy formatting rules (#2336)

## Issue Addressed

The latest version of Rust has new clippy rules & the codebase isn't up to date with them.

## Proposed Changes

Small formatting changes that clippy tells me are functionally equivalent

beacon_node/beacon_chain/src/builder.rs

@@ -306,8 +306,8 @@ where
             })?;
 
         let genesis = BeaconSnapshot {
-            beacon_block_root,
             beacon_block,
+            beacon_block_root,
             beacon_state,
         };