Add a comment explaining what autocloud.pm does

Signed-off-by: Adam Williamson <awilliam@redhat.com>

tests/autocloud.pm

@@ -15,6 +15,9 @@ sub _soft_fail_run {
 }
 
 sub run {
+    # This test is basically a recreation of exactly the test process
+    # autocloud used to use, via tunir and this tunir config:
+    # https://infrastructure.fedoraproject.org/cgit/ansible.git/tree/roles/autocloud/backend/files/fedora.txt?id=6e7c1b90593df8371fd34ed9484bd4da119236d3
     my $self = shift;
     bypass_1691487;
     # we need to use script_run as regular user