[20.10] update containerd binary to v1.6.19

Update hcsshim to v0.9.7 to include fix for graceful termination and pause containers

- release notes: https://github.com/containerd/containerd/releases/tag/v1.6.19
- full diff: https://github.com/containerd/containerd/compare/v1.6.18...v1.6.19

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit 3125aa0aefb3359d875798efb2655e51f0d0c4a8)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

hack/dockerfile/install/containerd.installer

@@ -15,7 +15,7 @@ set -e
 # the binary version you may also need to update the vendor version to pick up
 # bug fixes or new APIs, however, usually the Go packages are built from a
 # commit from the master branch.
-: "${CONTAINERD_VERSION:=v1.6.18}"
+: "${CONTAINERD_VERSION:=v1.6.19}"
 
 install_containerd() (
 	echo "Install containerd version $CONTAINERD_VERSION"