Make tests generic across an EthSpec

eth2/types/src/attestation_data_and_custody_bit.rs

@@ -2,14 +2,25 @@ use super::AttestationData;
 use crate::test_utils::TestRandom;
 
 use rand::RngCore;
-use serde_derive::Serialize;
+use serde_derive::{Deserialize, Serialize};
 use ssz_derive::{Decode, Encode};
 use tree_hash_derive::{CachedTreeHash, TreeHash};
 
 /// Used for pairing an attestation with a proof-of-custody.
 ///
 /// Spec v0.5.1
-#[derive(Debug, Clone, PartialEq, Default, Serialize, Encode, Decode, TreeHash, CachedTreeHash)]
+#[derive(
+    Debug,
+    Clone,
+    PartialEq,
+    Default,
+    Serialize,
+    Deserialize,
+    Encode,
+    Decode,
+    TreeHash,
+    CachedTreeHash,
+)]
 pub struct AttestationDataAndCustodyBit {
     pub data: AttestationData,
     pub custody_bit: bool,