chore: update Windows containerd package v1.6 to v1.6.21

Author: AbelHu

parts/windows/windowscsehelper.ps1

@@ -57,7 +57,7 @@ $global:WINDOWS_CSE_ERROR_RESIZE_OS_DRIVE=52
 
 # NOTE: KubernetesVersion does not contain "v"
 $global:MinimalKubernetesVersionWithLatestContainerd = "1.27.0" # Will change it to the correct version when we support new Windows containerd version
-$global:StableContainerdPackage = "v0.0.56/binaries/containerd-v0.0.56-windows-amd64.tar.gz"
+$global:StableContainerdPackage = "v1.6.21-azure.1/binaries/containerd-v1.6.21-azure.1-windows-amd64.tar.gz"
 # The latest containerd version
 $global:LatestContainerdPackage = "v1.7.1-azure.1/binaries/containerd-v1.7.1-azure.1-windows-amd64.tar.gz"
 

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

@@ -10,7 +10,7 @@ if (-not ($validSKU -contains $windowsSKU)) {
 
 # defaultContainerdPackageUrl refers to the stable containerd package used to pull and cache container images
 # Add cache for another containerd version which is not installed by default
-$global:defaultContainerdPackageUrl = "https://acs-mirror.azureedge.net/containerd/windows/v0.0.56/binaries/containerd-v0.0.56-windows-amd64.tar.gz"
+$global:defaultContainerdPackageUrl = "https://acs-mirror.azureedge.net/containerd/windows/v1.6.21-azure.1/binaries/containerd-v1.6.21-azure.1-windows-amd64.tar.gz"
 
 # Windows Server 2019 update history can be found at https://support.microsoft.com/en-us/help/4464619
 # Windows Server 2022 update history can be found at https://support.microsoft.com/en-us/topic/windows-server-2022-update-history-e1caa597-00c5-4ab9-9f3e-8212fe80b2ee