removed exit on fail "sh -e" for dhclient-script

The Bug causing dhclient to recall BIND has been identified:
dhclient-script runs with #!/bin/sh -e, causing setup_interface
to fail if no hostname is provided by dhcp as it is the last statement
in that function.

modules.d/40network/dhclient-script

@@ -1,4 +1,4 @@
-#!/bin/sh -e
+#!/bin/sh 
 
 setup_interface() {
     ip=$new_ip_address