Update node flags to use dev-mode instead of deprecated consensus params

The old flags consensus-sample-size, consensus-quorum-size, and
consensus-commit-threshold have been replaced with dev-mode and
poa-single-node-mode in luxd v1.21.0.

local/default/flags.json

@@ -7,11 +7,8 @@
   "index-enabled":true,
   "log-display-level":"ERROR",
   "log-level": "DEBUG",
-  "consensus-sample-size": 1,
-  "consensus-quorum-size": 1,
-  "consensus-commit-threshold": 1,
-  "sybil-protection-enabled": false,
+  "dev-mode": true,
+  "poa-single-node-mode": true,
   "network-health-min-conn-peers": 0,
-  "skip-bootstrap": true,
-  "poa-single-node-mode": true
+  "skip-bootstrap": true
 }

stacks/lux-l1-l2-local.yaml

@@ -12,9 +12,8 @@ engines:
     wait_healthy: true
     extra:
       staking-enabled: false
-      sybil-protection-enabled: false
-      consensus-sample-size: 1
-      consensus-quorum-size: 1
+      dev-mode: true
+      poa-single-node-mode: true
       
   - name: lux-l2-op
     type: op