fix: prevent conflicting GKE CIDR in examples

modules/gh-runner-gke/README.md

@@ -95,6 +95,7 @@ This example shows how to deploy Self Hosted Runners on GKE that supports Docker
 | ip\_range\_services\_cider | The secondary ip range cidr to use for services | `string` | `"192.168.64.0/18"` | no |
 | ip\_range\_services\_name | The secondary ip range to use for services | `string` | `"ip-range-scv"` | no |
 | machine\_type | Machine type for runner node pool | `string` | `"n1-standard-4"` | no |
+| master\_ipv4\_cidr\_block | The IP range in CIDR notation to use for the hosted master network of the GKE cluster. | `string` | `"10.1.0.0/28"` | no |
 | max\_node\_count | Maximum number of nodes in the runner node pool | `number` | `4` | no |
 | min\_node\_count | Minimum number of nodes in the runner node pool | `number` | `2` | no |
 | network\_name | Name for the VPC network | `string` | `"runner-network"` | no |

modules/gh-runner-gke/main.tf

@@ -59,6 +59,7 @@ module "runner-cluster" {
   zones                    = var.zones
   enable_private_endpoint  = var.enable_private_endpoint
   enable_private_nodes     = var.enable_private_nodes
+  master_ipv4_cidr_block   = var.master_ipv4_cidr_block
   network                  = local.network_name
   network_project_id       = var.subnetwork_project != "" ? var.subnetwork_project : var.project_id
   subnetwork               = local.subnet_name

modules/gh-runner-gke/variables.tf

@@ -195,3 +195,9 @@ variable "enable_private_nodes" {
   type        = bool
   default     = false
 }
+
+variable "master_ipv4_cidr_block" {
+  description = "The IP range in CIDR notation to use for the hosted master network of the GKE cluster."
+  type        = string
+  default     = "10.1.0.0/28"
+}