Remove separate dh-systemd dependency since this is obsolete on newer Debian anyway.

debian/control

@@ -3,7 +3,7 @@ Maintainer: Adam Ierymenko <[email protected]>
 Section: net
 Priority: optional
 Standards-Version: 3.9.6
-Build-Depends: debhelper (>= 9), dh-systemd
+Build-Depends: debhelper (>= 9)
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