TT#169100 Force dependency on systemd-timesyncd as systemd demoted it in 247.3-7

See https://metadata.ftp-master.debian.org/changelogs//main/s/systemd/systemd_247.3-7_changelog

>  Demote systemd-timesyncd from Depends to Recommends.
>
>  This avoids a dependency cycle between systemd and systemd-timesyncd and
>  thus makes dist upgrades more predictable and robust.
>  It also allows minimal, systemd based containers where no NTP client is
>  strictly necessary.
>  To ensure that systemd-timesyncd is installed in a default installation
>  created by d-i, bump its priority to standard.
>  (Closes: #986651, #993947)

Change-Id: I1db174936605fd1012ac54c7ee5f147e82daa619
(cherry picked from commit 18d2e57aaa)
(cherry picked from commit 70d8a96a7a)

debian/control

@@ -385,7 +385,7 @@ Depends:
  systemd,
  systemd-coredump,
  systemd-sysv,
- systemd-timesyncd | systemd,
+ systemd-timesyncd,
  telegraf,
  victoria-metrics,
  zstd,
@@ -482,7 +482,7 @@ Depends:
  systemd,
  systemd-coredump,
  systemd-sysv,
- systemd-timesyncd | systemd,
+ systemd-timesyncd,
  telegraf,
  victoria-metrics,
  zstd,