chore(contract_manager): change Blast network rpc (#1354)

contract_manager/store/chains/EvmChains.yaml

@@ -480,7 +480,7 @@
   type: EvmChain
 - id: blast
   mainnet: true
-  rpcUrl: https://falling-small-wildflower.blast-mainnet.quiknode.pro/$ENV_BLAST_MAINNET_API_KEY
+  rpcUrl: https://rpc.blast.io
   networkId: 81457
   type: EvmChain
 - id: merlin_testnet