Comment 11 for bug 1824255

This is still a problem for snapcraft hooks, because even when I have a part that stages the hooks into $SNAPCRAFT_PART_INSTALL/snap/hooks/<hook-name> the generated hook in $SNAPCRAFT_PRIME/meta/hooks/<hook-name> just looks like this:

```
#!/bin/sh
exec "$SNAP/snap/hooks/install" "$@"
```

and the generated snap.yaml doesn't specify the install hook at all, thus it also doesn't specify command-chain, so all snapcraft is doing in this situation is creating another shell script to call the first shell script.

This is with snapcraft edge:

```
$ snapcraft version
snapcraft, version 3.9.2+git139.g621eea18
$ snap info snapcraft | grep installed
installed: 3.9.2+git139.g621eea18 (3828) 62MB classic
```