fix: bump tier-1-cluster LimitRange max to 8Gi for MySQL 6Gi limit

Kyverno's tier-1-cluster LimitRange had max=4Gi which blocked
mysql-cluster-2 from starting after we bumped MySQL to 6Gi limit.
Also added custom LimitRange in dbaas stack (for when Terraform
manages it directly).

stacks/dbaas/modules/dbaas/main.tf

@@ -27,6 +27,29 @@ resource "kubernetes_namespace" "dbaas" {
   }
 }
 
+# Override Kyverno tier-1-cluster LimitRange (max 4Gi) to allow MySQL 6Gi limit
+resource "kubernetes_limit_range" "dbaas" {
+  metadata {
+    name      = "tier-defaults"
+    namespace = kubernetes_namespace.dbaas.metadata[0].name
+  }
+  spec {
+    limit {
+      type = "Container"
+      default = {
+        memory = "256Mi"
+      }
+      default_request = {
+        cpu    = "50m"
+        memory = "256Mi"
+      }
+      max = {
+        memory = "8Gi"
+      }
+    }
+  }
+}
+
 resource "kubernetes_resource_quota" "dbaas" {
   metadata {
     name      = "dbaas-quota"

stacks/kyverno/modules/kyverno/resource-governance.tf

@@ -208,7 +208,7 @@ resource "kubernetes_manifest" "generate_limitrange_by_tier" {
                       memory = "256Mi"
                     }
                     max = {
-                      memory = "4Gi"
+                      memory = "8Gi"
                     }
                   }
                 ]