[ci skip] fix redis OOMKilled: increase memory limits to 2Gi

Redis was CrashLoopBackOff due to OOMKilled - 512Mi limit was
insufficient for 650MB RDB dataset plus redis-stack modules.

stacks/platform/modules/redis/main.tf

@@ -52,12 +52,12 @@ resource "kubernetes_deployment" "redis" {
 
           resources {
             requests = {
-              cpu    = "100m"
-              memory = "128Mi"
+              cpu    = "200m"
+              memory = "1Gi"
             }
             limits = {
-              cpu    = "500m"
-              memory = "512Mi"
+              cpu    = "1"
+              memory = "2Gi"
             }
           }