test(ctb): unskip testCannot_AppendWithUnmatchedBlockhash (#2899)

packages/contracts-bedrock/.gas-snapshot

@@ -57,14 +57,15 @@ L2CrossDomainMessenger_Test:test_L2MessengerSendMessage() (gas: 119682)
 L2CrossDomainMessenger_Test:test_L2MessengerTwiceSendMessage() (gas: 133142)
 L2CrossDomainMessenger_Test:test_L2MessengerXDomainSenderReverts() (gas: 10599)
 L2CrossDomainMessenger_Test:test_L2MessengerxDomainMessageSenderResets() (gas: 54881)
+L2OutputOracleTest:testCannot_AppendWithUnmatchedBlockhash() (gas: 26799)
 L2OutputOracleTest:testCannot_appendEmptyOutput() (gas: 24119)
-L2OutputOracleTest:testCannot_appendFutureTimetamp() (gas: 26086)
-L2OutputOracleTest:testCannot_appendOnWrongFork() (gas: 26371)
+L2OutputOracleTest:testCannot_appendFutureTimetamp() (gas: 26043)
+L2OutputOracleTest:testCannot_appendOnWrongFork() (gas: 26348)
 L2OutputOracleTest:testCannot_appendOutputIfNotSequencer() (gas: 23510)
-L2OutputOracleTest:testCannot_appendUnexpectedBlockNumber() (gas: 25995)
-L2OutputOracleTest:testCannot_deleteL2Output_ifNotOwner() (gas: 24777)
+L2OutputOracleTest:testCannot_appendUnexpectedBlockNumber() (gas: 25951)
+L2OutputOracleTest:testCannot_deleteL2Output_ifNotOwner() (gas: 24799)
 L2OutputOracleTest:testCannot_deleteL2Output_withWrongRoot() (gas: 91091)
-L2OutputOracleTest:testCannot_deleteL2Output_withWrongTime() (gas: 87084)
+L2OutputOracleTest:testCannot_deleteL2Output_withWrongTime() (gas: 87040)
 L2OutputOracleTest:test_appendWithBlockhashAndHeight() (gas: 75017)
 L2OutputOracleTest:test_appendingAnotherOutput() (gas: 76817)
 L2OutputOracleTest:test_changeSequencer() (gas: 55776)
@@ -74,7 +75,7 @@ L2OutputOracleTest:test_deleteL2Output() (gas: 76516)
 L2OutputOracleTest:test_getL2Output() (gas: 82924)
 L2OutputOracleTest:test_latestBlockNumber() (gas: 76220)
 L2OutputOracleTest:test_nextBlockNumber() (gas: 15144)
-L2OutputOracleTest:test_updateOwner() (gas: 34580)
+L2OutputOracleTest:test_updateOwner() (gas: 34602)
 L2OutputOracleUpgradeable_Test:test_cannotInitImpl() (gas: 8476)
 L2OutputOracleUpgradeable_Test:test_cannotInitProxy() (gas: 13453)
 L2OutputOracleUpgradeable_Test:test_initValuesOnProxy() (gas: 38906)

packages/contracts-bedrock/contracts/test/L2OutputOracle.t.sol

@@ -233,9 +233,7 @@ contract L2OutputOracleTest is L2OutputOracle_Initializer {
 
     // Test: appendL2Output fails when given valid input, but the block hash and number do not
     // match.
-    // This tests is disabled (w/ skip_ prefix) because all blocks in Foundry currently have a
-    // blockhash of zero.
-    function skip_testCannot_AppendWithUnmatchedBlockhash() external {
+    function testCannot_AppendWithUnmatchedBlockhash() external {
         // Move ahead to block 100 so that we can reference historical blocks
         vm.roll(100);
 
@@ -248,6 +246,7 @@ contract L2OutputOracleTest is L2OutputOracle_Initializer {
         vm.prank(sequencer);
 
         // This will fail when foundry no longer returns zerod block hashes
+        vm.expectRevert("OutputOracle: Blockhash does not match the hash at the expected height.");
         oracle.appendL2Output(nonZeroHash, nextBlockNumber, l1BlockHash, l1BlockNumber - 1);
     }