fix(fast-inbox): drop AZTEC_INBOX_LAG reads from the L1 deploy-script tests (A-1388)

The env sweep removed AZTEC_INBOX_LAG from scripts/network-defaults.json but
both deploy-script test setUps still readUint the key, which reverts
(vm.parseJsonUint on a missing path), failing the suites before any test
runs. The deploy configuration no longer consumes the env var.

Author: spalladino

l1-contracts/test/script/DeployAztecL1Contracts.t.sol

@@ -30,7 +30,6 @@ contract DeployAztecL1ContractsTest is Test {
     // Timing config
     vm.setEnv("AZTEC_SLOT_DURATION", vm.toString(json.readUint(".AZTEC_SLOT_DURATION")));
     vm.setEnv("AZTEC_EPOCH_DURATION", vm.toString(json.readUint(".AZTEC_EPOCH_DURATION")));
-    vm.setEnv("AZTEC_INBOX_LAG", vm.toString(json.readUint(".AZTEC_INBOX_LAG")));
     vm.setEnv("AZTEC_PROOF_SUBMISSION_EPOCHS", vm.toString(json.readUint(".AZTEC_PROOF_SUBMISSION_EPOCHS")));
 
     // Validator config

l1-contracts/test/script/DeployRollupForUpgrade.t.sol

@@ -41,7 +41,6 @@ contract DeployRollupForUpgradeTest is Test {
     // Timing config
     vm.setEnv("AZTEC_SLOT_DURATION", vm.toString(json.readUint(".AZTEC_SLOT_DURATION")));
     vm.setEnv("AZTEC_EPOCH_DURATION", vm.toString(json.readUint(".AZTEC_EPOCH_DURATION")));
-    vm.setEnv("AZTEC_INBOX_LAG", vm.toString(json.readUint(".AZTEC_INBOX_LAG")));
     vm.setEnv("AZTEC_PROOF_SUBMISSION_EPOCHS", vm.toString(json.readUint(".AZTEC_PROOF_SUBMISSION_EPOCHS")));
 
     // Validator config