remove uid, gid from rsyncd.conf for swift user

The rsync prior to v3.1.0 the uid/gid parameter have no effect at
all if it runs as normal(non-root) user.

Since v3.1.0 these parameter are problematic for normal user
because now rsync, regardless of root or non-root, if the
parameters are given then it just tries to call setgroups() which
is not possible for normal user so errors may occur.

    swift-object-replicator: @ERROR: setgroups failed\u0000
    swift-object-replicator: rsync error: error starting
    client-server protocol (code 5) at main.c(1648)
    [sender=3.1.2]\u0000

Either way, these parameters are not needed for swift-rsync
container.

Change-Id: Ia7fe9f06d7a21a55f52b90c2cc1b2498300e6532
Signed-off-by: Minho Ban <mhban@samsung.com>

ansible/roles/swift/templates/rsyncd.conf.j2

-uid = swift
-gid = swift
 address = {{ api_interface_address }}
 
 {% if inventory_hostname in groups['swift-account-server'] %}