docs: fix broken reference to backup_remote

while restructuring the docs, explicit title wasn't included in the
correct file

fixes commit 04e24b14f0

Signed-off-by: Oguz Bektas <o.bektas@proxmox.com>

docs/managing-remotes.rst

@@ -1,6 +1,8 @@
 Managing Remotes
 ================
 
+.. _backup_remote:
+
 :term:`Remote`
 --------------
 

docs/network-management.rst

@@ -86,6 +86,3 @@ You can also configure DNS settings, from the **DNS** section
 of **Configuration** or by using the ``dns`` subcommand of
 ``proxmox-backup-manager``.
 
-.. _backup_remote:
-
-