sort entity list again before giving it to comm(1)

Apparently `holo scan` sorts stuff differently than sort(1).
In particular, I see that `holo scan --short` on one of my servers lists

  file:/etc/munin/munin-node.conf
  file:/etc/munin/munin.conf

in that order, but `holo scan --short | sort` puts it the other way
around.

Author: majewsky

util/distribution-integration/alpm-hook.sh

@@ -6,5 +6,5 @@ comm -12 \
      <(# changed files come from stdin (but without leading slash!)
        sort | sed 's+^+/+') \
      <(# enumerate files that are managed by holo-files
-       holo scan --short | sed -n 's/^file://p') \
+       holo scan --short | sed -n 's/^file://p' | sort) \
 | sed 's/^/file:/' | xargs -r holo apply