fix: Add missing mixed_instances_policy parameter to the root module (#1808)

examples/self_managed_node_group/main.tf

@@ -118,6 +118,36 @@ module "eks" {
       EOT
     }
 
+    mixed = {
+      name = "mixed"
+
+      min_size     = 1
+      max_size     = 5
+      desired_size = 2
+
+      bootstrap_extra_args = "--kubelet-extra-args '--node-labels=node.kubernetes.io/lifecycle=spot'"
+
+      use_mixed_instances_policy = true
+      mixed_instances_policy = {
+        instances_distribution = {
+          on_demand_base_capacity                  = 0
+          on_demand_percentage_above_base_capacity = 20
+          spot_allocation_strategy                 = "capacity-optimized"
+        }
+
+        override = [
+          {
+            instance_type     = "m5.large"
+            weighted_capacity = "1"
+          },
+          {
+            instance_type     = "m6i.large"
+            weighted_capacity = "2"
+          },
+        ]
+      }
+    }
+
     # Complete
     complete = {
       name            = "complete-self-mng"