Update containerd to v1.1.4

Fixes a potential content store bug, backported from 1.2

- v1.1.3 release notes: https://github.com/containerd/containerd/releases/tag/v1.1.3
- v1.1.4 release notes: https://github.com/containerd/containerd/releases/tag/v1.1.4

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

hack/dockerfile/install/containerd.installer

@@ -4,7 +4,7 @@
 # containerd is also pinned in vendor.conf. When updating the binary
 # version you may also need to update the vendor version to pick up bug
 # fixes or new APIs.
-CONTAINERD_COMMIT=468a545b9edcd5932818eb9de8e72413e616e86e # v1.1.2
+CONTAINERD_COMMIT=9f2e07b1fc1342d1c48fe4d7bbb94cb6d1bf278b # v1.1.4
 
 install_containerd() {
 	echo "Install containerd version $CONTAINERD_COMMIT"