systemd: Start after the dump manager

In case --sink=dbus is supplied.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: I7cb13afecca6246e85dad0b054c708160c32191b
diff --git a/systemd/system/debug-trigger@.service b/systemd/system/debug-trigger@.service
index b9ec40e..6e40474 100644
--- a/systemd/system/debug-trigger@.service
+++ b/systemd/system/debug-trigger@.service
@@ -1,5 +1,6 @@
 [Unit]
 Description=BMC Debug Trigger
+After=xyz.openbmc_project.Dump.Manager.service
 
 [Service]
 Type=simple