l2geth: skip clique consensus rule

There is a rule in the Clique `verifyHeader` function
that will prevent blocks with a timestamp in the future
from being included in the chain. We want to ensure that
this check is being the `UsingOVM` flag as to prevent
blocks from ever being considered not valid.

.changeset/many-queens-own.md

+---
+'@eth-optimism/l2geth': patch
+---
+
+Ensure that L2 geth doesn't reject blocks from the future

l2geth/consensus/clique/clique.go

@@ -249,7 +249,7 @@ func (c *Clique) verifyHeader(chain consensus.ChainReader, header *types.Header,
 	}
 	number := header.Number.Uint64()
 
-	if vm.UsingOVM {
+	if !vm.UsingOVM {
 		// Don't waste time checking blocks from the future
 		if header.Time > uint64(time.Now().Unix()) {
 			return consensus.ErrFutureBlock