fix(ingress-nginx): Upgrade ingress-nginx to v1.12.1 and webhook certgen image to v1.5.2

This commit upgrades ingress-nginx to version v1.12.1, addressing multiple critical vulnerabilities including CVE-2025-1974, CVE-2025-1097, CVE-2025-1098, CVE-2025-24513, and CVE-2025-24514 as detailed in the ingress-nginx release notes: https://github.com/kubernetes/ingress-nginx/releases/tag/controller-v1.12.1

Important Notes:
- Fixing CVE-2025-1974 required disabling validation of the generated NGINX configuration during validation of Ingress resources. Invalid Ingress resources may stop the NGINX configuration from being updated.
- Recommended mitigations include enabling annotation validation and disabling snippet annotations.

Alongside this upgrade, the `ingress_nginx_kube_webhook_certgen_image_tag` has been updated to v1.5.2 for compatibility, based on: kubernetes/ingress-nginx#13066

Changelog:
- Updated ingress-nginx version to v1.12.1 in Kubespray.
- Updated `ingress_nginx_kube_webhook_certgen_image_tag` in `roles/kubespray-defaults/defaults/main/download.yml` to v1.5.2.

Fixes: kubernetes-sigs#12073

Author: farshadasadpour

README.md

@@ -129,7 +129,7 @@ Note:
 - Application
   - [cert-manager](https://github.com/jetstack/cert-manager) 1.15.3
   - [coredns](https://github.com/coredns/coredns) 1.11.3
-  - [ingress-nginx](https://github.com/kubernetes/ingress-nginx) 1.12.0
+  - [ingress-nginx](https://github.com/kubernetes/ingress-nginx) 1.12.1
   - [argocd](https://argoproj.github.io/) 2.14.5
   - [helm](https://helm.sh/) 3.16.4
   - [metallb](https://metallb.universe.tf/) 0.13.9

roles/kubespray-defaults/defaults/main/download.yml

@@ -323,13 +323,13 @@ rbd_provisioner_image_tag: "v{{ rbd_provisioner_version }}"
 local_path_provisioner_version: "0.0.24"
 local_path_provisioner_image_repo: "{{ docker_image_repo }}/rancher/local-path-provisioner"
 local_path_provisioner_image_tag: "v{{ local_path_provisioner_version }}"
-ingress_nginx_version: "1.12.0"
+ingress_nginx_version: "1.12.1"
 ingress_nginx_controller_image_repo: "{{ kube_image_repo }}/ingress-nginx/controller"
 ingress_nginx_opentelemetry_image_repo: "{{ kube_image_repo }}/ingress-nginx/opentelemetry"
 ingress_nginx_controller_image_tag: "v{{ ingress_nginx_version }}"
 ingress_nginx_opentelemetry_image_tag: "v20230721-3e2062ee5"
 ingress_nginx_kube_webhook_certgen_image_repo: "{{ kube_image_repo }}/ingress-nginx/kube-webhook-certgen"
-ingress_nginx_kube_webhook_certgen_image_tag: "v1.5.0"
+ingress_nginx_kube_webhook_certgen_image_tag: "v1.5.2"
 alb_ingress_image_repo: "{{ docker_image_repo }}/amazon/aws-alb-ingress-controller"
 alb_ingress_image_tag: "v1.1.9"
 cert_manager_version: "1.15.3"