Try fixing tests

Author: michaelsproul

beacon_node/beacon_chain/tests/block_verification.rs

@@ -206,6 +206,10 @@ fn update_blob_signed_header<E: EthSpec>(
     signed_block: &SignedBeaconBlock<E>,
     blobs: &mut BlobSidecarList<E>,
 ) {
+    // Required to prevent as_mut_slice being called on an uninitialized list. Yuck.
+    if blobs.is_empty() {
+        return;
+    }
     for old_blob_sidecar in blobs.as_mut_slice().unwrap() {
         let new_blob = Arc::new(BlobSidecar::<E> {
             index: old_blob_sidecar.index,

beacon_node/execution_layer/src/test_utils/execution_block_generator.rs

@@ -672,7 +672,7 @@ impl<E: EthSpec> ExecutionBlockGenerator<E> {
             // get random number between 0 and Max Blobs
             let mut rng = self.rng.lock();
             // TODO(pawan): thread the chainspec value here somehow
-            let num_blobs = rng.gen::<usize>() % 6;
+            let num_blobs = rng.gen::<usize>() % (6 + 1);
             let (bundle, transactions) = generate_blobs(num_blobs)?;
             for tx in Vec::from(transactions) {
                 execution_payload