downgrade cached version of azure-vnet

vhdbuilder/packer/generate-windows-vhd-configuration.ps1

@@ -139,12 +139,12 @@ $global:imagesToPull += @(
     # CNS (Container Networking Service) Owner: evanbaker
     "mcr.microsoft.com/containernetworking/azure-cns:v1.4.58",
     "mcr.microsoft.com/containernetworking/azure-cns:v1.5.38",
-    "mcr.microsoft.com/containernetworking/azure-cns:v1.6.18",
+    "mcr.microsoft.com/containernetworking/azure-cns:v1.6.13",
 
     # CNI installer for azure-vnet. Owner: evanbaker
     "mcr.microsoft.com/containernetworking/azure-cni:v1.4.58",
     "mcr.microsoft.com/containernetworking/azure-cni:v1.5.38",
-    "mcr.microsoft.com/containernetworking/azure-cni:v1.6.18"
+    "mcr.microsoft.com/containernetworking/azure-cni:v1.6.13"
 )
 
 $global:map = @{
@@ -206,7 +206,7 @@ $global:map = @{
     "c:\akse-cache\win-vnet-cni\" = @(
         # Azure CNI v1 (legacy)
         "https://acs-mirror.azureedge.net/azure-cni/v1.5.38/binaries/azure-vnet-cni-windows-amd64-v1.5.38.zip",
-        "https://acs-mirror.azureedge.net/azure-cni/v1.6.18/binaries/azure-vnet-cni-windows-amd64-v1.6.13.zip",
+        "https://acs-mirror.azureedge.net/azure-cni/v1.6.13/binaries/azure-vnet-cni-windows-amd64-v1.6.13.zip",
         # Azure CNI v2 (pod subnet)
         "https://acs-mirror.azureedge.net/azure-cni/v1.4.58/binaries/azure-vnet-cni-swift-windows-amd64-v1.4.58.zip",
         # Azure CNI for Overlay