automatic: Return an error when transaction fails (RhBug:2170093)

In case of no global error occurred within the transaction, we still need to check state of individual transaction items for any failure.

This is matching the logic in `BaseCli.do_transaction` method, where the error is emitted after printing the transaction summary.

= changelog =
msg: automatic: Return an error when transaction fails
type: bugfix
resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2170093

dnf/automatic/main.py

@@ -351,6 +351,13 @@ def main(args):
 
             gpgsigcheck(base, trans.install_set)
             base.do_transaction()
+
+            # In case of no global error occurred within the transaction,
+            # we need to check state of individual transaction items.
+            for tsi in trans:
+                if tsi.state == libdnf.transaction.TransactionItemState_ERROR:
+                    raise dnf.exceptions.Error(_('Transaction failed'))
+
             emitters.notify_applied()
             emitters.commit()