Merge parent and current sync lookups (#5655)

* Drop lookup type trait for a simple arg

* Drop reconstructed for processing

* Send parent blocks one by one

* Merge current and parent lookups

* Merge current and parent lookups clean up todos

* Merge current and parent lookups tests

* Merge remote-tracking branch 'origin/unstable' into sync-merged-lookup

* Merge branch 'unstable' of https://github.com/sigp/lighthouse into sync-merged-lookup

* fix compile after merge

* #5655 pr review (#26)

* fix compile after merge

* remove todos, fix typos etc

* fix compile

* stable rng

* delete TODO and unfilled out test

* make download result a struct

* enums instead of bools as params

* fix comment

* Various fixes

* Track ignored child components

* Track dropped lookup reason as metric

* fix test

* add comment describing behavior of avail check error

*  update ordering

beacon_node/beacon_chain/src/blob_verification.rs

@@ -571,6 +571,14 @@ pub fn validate_blob_sidecar_for_gossip<T: BeaconChainTypes>(
         });
     }
 
+    // Kzg verification for gossip blob sidecar
+    let kzg = chain
+        .kzg
+        .as_ref()
+        .ok_or(GossipBlobError::KzgNotInitialized)?;
+    let kzg_verified_blob = KzgVerifiedBlob::new(blob_sidecar.clone(), kzg, seen_timestamp)
+        .map_err(GossipBlobError::KzgError)?;
+
     chain
         .observed_slashable
         .write()
@@ -605,14 +613,6 @@ pub fn validate_blob_sidecar_for_gossip<T: BeaconChainTypes>(
         });
     }
 
-    // Kzg verification for gossip blob sidecar
-    let kzg = chain
-        .kzg
-        .as_ref()
-        .ok_or(GossipBlobError::KzgNotInitialized)?;
-    let kzg_verified_blob = KzgVerifiedBlob::new(blob_sidecar, kzg, seen_timestamp)
-        .map_err(GossipBlobError::KzgError)?;
-
     Ok(GossipVerifiedBlob {
         block_root,
         blob: kzg_verified_blob,