Installation breaks on /var/lib/dpkg/info/isc-dhcp-server.postinst

Line 74:
test ! -x /sbin/restorecon || restorecon /var/lib/dhcp/dhcpd.leases

# echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
# whereis restorecon
restorecon: /usr/sbin/restorecon /usr/share/man/man8/restorecon.8.gz

restorecon is not in /sbin

Editing line 74 and removing the path it works:
test ! -x restorecon || restorecon /var/lib/dhcp/dhcpd.leases

Currently I think it's expected that /sbin will be a symlink to /usr/sbin so
this will work in all systems with a regular configuration.

But having one reference to it with full path and another to it without a path
is a bug in any case so the proposed fix is reasonable.

A bigger problem is that the file will not exist on the first install of the
package and therefore restorecon won't be able to do anything.  A solution to
that is to have the following line before the restorecon line:

touch /var/lib/dhcp/dhcpd.leases

Dear submitter,

as the package isc-dhcp has just been removed from the Debian archive
unstable we hereby close the associated bug reports.  We are sorry
that we couldn't deal with your issue properly.

For details on the removal, please see https://bugs.debian.org/1143544

The version of this package that was in Debian prior to this removal
can still be found using https://snapshot.debian.org/.

Please note that the changes have been done on the master archive and
will not propagate to any mirrors until the next dinstall run at the
earliest.

This message was generated automatically; if you believe that there is
a problem with it please contact the archive administrators by mailing
ftpmaster@ftp-master.debian.org.

Debian distribution maintenance software
pp.
Thorsten Alteholz (the ftpmaster behind the curtain)