s4:tests: Avoid passing unnecessary env variables to auth_log tests

s4:tests: Avoid passing unnecessary env variables to auth_log tests

These tests all use the ncalrpc connection, so they're always testing a
connection that's local to the server-side. Therefore passing in the
CLIENT_IP and SOCKET_WRAPPER_DEFAULT_IFACE variables (in order to try to
simulate a client connecting) is unnecessary.

Signed-off-by: Tim Beale <timbeale@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>