core/evm: RANDOM opcode (EIP-4399) (#24141)

* core: implement eip-4399 random opcode

* core: make vmconfig threadsafe

* core: miner: pass vmConfig by value not reference

* all: enable 4399 by Rules

* core: remove diff (f)

* tests: set proper difficulty (f)

* smaller diff (f)

* eth/catalyst: nit

* core: make RANDOM a pointer which is only set post-merge

* cmd/evm/internal/t8ntool: fix t8n tracing of 4399

* tests: set difficulty

* cmd/evm/internal/t8ntool: check that baserules are london before applying the merge chainrules

consensus/beacon/consensus.go

@@ -43,7 +43,6 @@ var (
 // error types into the consensus package.
 var (
 	errTooManyUncles    = errors.New("too many uncles")
-	errInvalidMixDigest = errors.New("invalid mix digest")
 	errInvalidNonce     = errors.New("invalid nonce")
 	errInvalidUncleHash = errors.New("invalid uncle hash")
 )
@@ -182,10 +181,7 @@ func (beacon *Beacon) verifyHeader(chain consensus.ChainHeaderReader, header, pa
 	if len(header.Extra) > 32 {
 		return fmt.Errorf("extra-data longer than 32 bytes (%d)", len(header.Extra))
 	}
-	// Verify the seal parts. Ensure the mixhash, nonce and uncle hash are the expected value.
-	if header.MixDigest != (common.Hash{}) {
-		return errInvalidMixDigest
-	}
+	// Verify the seal parts. Ensure the nonce and uncle hash are the expected value.
 	if header.Nonce != beaconNonce {
 		return errInvalidNonce
 	}