Rename random to prev_randao (#3040)

## Issue Addressed

As discussed on last-night's consensus call, the testnets next week will target the [Kiln Spec v2](https://hackmd.io/@n0ble/kiln-spec).

Presently, we support Kiln V1. V2 is backwards compatible, except for renaming `random` to `prev_randao` in:

- https://github.com/ethereum/execution-apis/pull/180
- https://github.com/ethereum/consensus-specs/pull/2835

With this PR we'll no longer be compatible with the existing Kintsugi and Kiln testnets, however we'll be ready for the testnets next week. I raised this breaking change in the call last night, we are all keen to move forward and break things.

We now target the [`merge-kiln-v2`](https://github.com/MariusVanDerWijden/go-ethereum/tree/merge-kiln-v2) branch for interop with Geth. This required adding the `--http.aauthport` to the tester to avoid a port conflict at startup.

### Changes to exec integration tests

There's some change in the `merge-kiln-v2` version of Geth that means it can't compile on a vanilla Github runner. Bumping the `go` version on the runner solved this issue.

Whilst addressing this, I refactored the `testing/execution_integration` crate to be a *binary* rather than a *library* with tests. This means that we don't need to run the `build.rs` and build Geth whenever someone runs `make lint` or `make test-release`. This is nice for everyday users, but it's also nice for CI so that we can have a specific runner for these tests and we don't need to ensure *all* runners support everything required to build all execution clients.

## More Info

- [x] ~~EF tests are failing since the rename has broken some tests that reference the old field name. I have been told there will be new tests released in the coming days (25/02/22 or 26/02/22).~~

consensus/fork_choice/src/fork_choice.rs

@@ -1,4 +1,4 @@
-use crate::ForkChoiceStore;
+use crate::{ForkChoiceStore, InvalidationOperation};
 use proto_array::{Block as ProtoBlock, ExecutionStatus, ProtoArrayForkChoice};
 use ssz_derive::{Decode, Encode};
 use std::cmp::Ordering;
@@ -480,11 +480,10 @@ where
     /// See `ProtoArrayForkChoice::process_execution_payload_invalidation` for documentation.
     pub fn on_invalid_execution_payload(
         &mut self,
-        head_block_root: Hash256,
-        latest_valid_ancestor_root: Option<ExecutionBlockHash>,
+        op: &InvalidationOperation,
     ) -> Result<(), Error<T::Error>> {
         self.proto_array
-            .process_execution_payload_invalidation(head_block_root, latest_valid_ancestor_root)
+            .process_execution_payload_invalidation(op)
             .map_err(Error::FailedToProcessInvalidExecutionPayload)
     }
 
@@ -956,19 +955,19 @@ where
             return Ok(true);
         }
 
-        // If the block has an ancestor with a verified parent, import this block.
+        // If the parent block has execution enabled, always import the block.
         //
-        // TODO: This condition is not yet merged into the spec. See:
+        // TODO(bellatrix): this condition has not yet been merged into the spec.
         //
-        // https://github.com/ethereum/consensus-specs/pull/2841
+        // See:
         //
-        // ## Note
-        //
-        // If `block_parent_root` is unknown this iter will always return `None`.
+        // https://github.com/ethereum/consensus-specs/pull/2844
         if self
             .proto_array
-            .iter_nodes(block_parent_root)
-            .any(|node| node.execution_status.is_valid())
+            .get_block(block_parent_root)
+            .map_or(false, |parent| {
+                parent.execution_status.is_execution_enabled()
+            })
         {
             return Ok(true);
         }

consensus/fork_choice/src/lib.rs

@@ -6,4 +6,4 @@ pub use crate::fork_choice::{
     PayloadVerificationStatus, PersistedForkChoice, QueuedAttestation,
 };
 pub use fork_choice_store::ForkChoiceStore;
-pub use proto_array::Block as ProtoBlock;
+pub use proto_array::{Block as ProtoBlock, InvalidationOperation};