contracts-bedrock: fix zora-sepolia config

See explanation in https://github.com/ethereum-optimism/optimism/pull/8515

Related to:
- https://github.com/ethereum-optimism/optimism/pull/8519
- https://github.com/ethereum-optimism/optimism/pull/8520

Value sourced from:
https://sepolia.etherscan.io/address/0x2615B481Bd3E5A1C0C7Ca3Da1bdc663E8615Ade9#readProxyContract

Address sourced from:
https://github.com/ethereum-optimism/superchain-registry/blob/fb3433d89a72df5809255c065b4783fa393608d8/superchain/extra/addresses/sepolia/zora.json#L6C27-L6C69

packages/contracts-bedrock/deploy-config/zora-sepolia.json

@@ -23,7 +23,7 @@
   "l2GenesisRegolithTimeOffset": "0x0",
   "superchainConfigGuardian": "0x45eFFbD799Ab49122eeEAB75B78D9C56A187F9A7",
   "l2OutputOracleSubmissionInterval": 180,
-  "l2OutputOracleStartingTimestamp": -1,
+  "l2OutputOracleStartingTimestamp": 1698080004,
   "l2OutputOracleStartingBlockNumber": 0,
   "l2OutputOracleProposer": "0xe8326a5839175dE7f467e66D8bB443aa70DA1c3e",
   "sequencerFeeVaultWithdrawalNetwork": 0,