docs: Update how-to-use-kata-containers-with-firecracker.md

Removed the `` around containerd, because when you execute this as a
script it runs the containerd command within the script, which it should
not do.

Fixes #4217

Signed-off-by: Willem Dendauw <willem.dendauw@hotmail.com>

docs/how-to/how-to-use-kata-containers-with-firecracker.md

@@ -104,7 +104,7 @@ sudo dmsetup create "${POOL_NAME}" \
 
 cat << EOF
 #
-# Add this to your config.toml configuration file and restart `containerd` daemon
+# Add this to your config.toml configuration file and restart containerd daemon
 #
 [plugins]
   [plugins.devmapper]