Raise level of 'Found dependency...' lines

This way they always show up together with 'Found ordering cycle...'.
Ordering cycles are a serious error and a major pain to debug. If
quiet is enabled, only the first and the last line of output are
shown:

systemd[1]: Found ordering cycle on basic.target/start
systemd[1]: Breaking ordering cycle by deleting job timers.target/start
systemd[1]: Job timers.target/start deleted to break ordering cycle starting with basic.target/start

which isn't particularly enlightening. So just show the whole message
at the same level.

https://bugzilla.redhat.com/show_bug.cgi?id=1158206

src/core/transaction.c

@@ -376,7 +376,7 @@ static int transaction_verify_order_one(Transaction *tr, Job *j, Job *from, unsi
                 for (k = from; k; k = ((k->generation == generation && k->marker != k) ? k->marker : NULL)) {
 
                         /* logging for j not k here here to provide consistent narrative */
-                        log_info_unit(j->unit->id,
+                        log_warning_unit(j->unit->id,
                                          "Found dependency on %s/%s",
                                          k->unit->id, job_type_to_string(k->type));