contracts-bedrock: mainnet deployment

Latest contracts release deployed to mainnet. These are only
implementation addresses. The deploy config is updated with
the `systemConfigStartBlock` which should be set to the
block number that the contract was initialized in.
This happened in the following tx: https://etherscan.io/tx/0x76bceccd7d44656f5a129a600a6120091570b897c1d45c18cd7134cfe67c2537
which was included in block 17422444.

packages/contracts-bedrock/deploy-config/mainnet.json

@@ -38,5 +38,6 @@
   "gasPriceOracleScalar": 684000,
   "eip1559Denominator": 50,
   "eip1559Elasticity": 6,
-  "l2GenesisRegolithTimeOffset": "0x0"
+  "l2GenesisRegolithTimeOffset": "0x0",
+  "systemConfigStartBlock": 17422444
 }