Spec v1.7.0-alpha.6 and Gloas genesis (#9190)

Co-Authored-By: Josh King <josh@sigmaprime.io>

Co-Authored-By: Jimmy Chen <jchen.tc@gmail.com>

Co-Authored-By: Michael Sproul <michael@sigmaprime.io>

beacon_node/beacon_chain/src/pending_payload_envelopes.rs

@@ -105,6 +105,7 @@ mod tests {
                 execution_requests: ExecutionRequests::default(),
                 builder_index: 0,
                 beacon_block_root: Hash256::ZERO,
+                parent_beacon_block_root: Hash256::ZERO,
             },
             blobs: None,
         }