Removed stray postinst file

debian/postinst

-#!/bin/sh
-
-set -e
-
-case "$1" in
-configure)
-    addgroup --system --quiet user-meta-server
-    adduser --system --no-create-home --home /run/user-meta-server \
-      --disabled-password --disabled-login \
-      --quiet --ingroup user-meta-server user-meta-server
-
-    test -d /var/lib/user-meta-server || mkdir /var/lib/user-meta-server
-    chown user-meta-server.user-meta-server /var/lib/user-meta-server
-    chmod 750 /var/lib/user-meta-server
-
-    ;;
-esac
-
-#DEBHELPER#
-
-exit 0