Fix hardcoded pod infra version

Signed-off-by: bo.jiang <bo.jiang@daocloud.io>

roles/download/defaults/main/main.yml

@@ -114,7 +114,6 @@ flannel_version: "v0.22.0"
 flannel_cni_version: "v1.1.2"
 cni_version: "v1.3.0"
 weave_version: 2.8.1
-pod_infra_version: "3.9"
 
 cilium_version: "v1.13.4"
 cilium_cli_version: "v0.15.0"
@@ -132,6 +131,12 @@ skopeo_version: "v1.13.2"
 # Get kubernetes major version (i.e. 1.17.4 => 1.17)
 kube_major_version: "{{ kube_version | regex_replace('^v([0-9])+\\.([0-9]+)\\.[0-9]+', 'v\\1.\\2') }}"
 
+pod_infra_supported_version:
+  v1.27: "3.9"
+  v1.26: "3.9"
+  v1.25: "3.8"
+pod_infra_version: "{{ pod_infra_supported_version[kube_major_version] }}"
+
 etcd_supported_versions:
   v1.27: "v3.5.10"
   v1.26: "v3.5.10"