chore(contract_manager): fix Blast API env var (#1326)

Author: ali-behjati

contract_manager/store/chains/EvmChains.yaml

@@ -475,6 +475,6 @@
   type: EvmChain
 - id: blast
   mainnet: true
-  rpcUrl: https://falling-small-wildflower.blast-mainnet.quiknode.pro/${ENV_BLAST_MAINNET_API_KEY}/
+  rpcUrl: https://falling-small-wildflower.blast-mainnet.quiknode.pro/$ENV_BLAST_MAINNET_API_KEY
   networkId: 81457
   type: EvmChain