test/distro: Avoid race between display of ns_msg and netcat exiting

The shell might report 'nc -6 -l -p 9999 > /tmp/ns_msg' as done
even after the subsequent 'echo' is done: wait one second before
reading out /tmp/ns_msg, to ensure we read that instead of the
"Done" message.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

test/distro/debian

@@ -26,6 +26,7 @@ sleep	2
 host	echo "from_ns" | nc -q0 ::1 10000
 sleep	2
 host	echo
+sleep	1
 hout	NS_MSG cat /tmp/ns_msg
 check	[ __NS_MSG__ = "from_init" ]
 hostb	exit

test/distro/fedora

@@ -25,6 +25,7 @@ sleep	2
 host	echo "from_ns" | nc ::1 10000
 sleep	2
 host	echo
+sleep	1
 hout	NS_MSG cat /tmp/ns_msg
 check	[ __NS_MSG__ = "from_init" ]
 hostb	exit

test/distro/opensuse

@@ -25,6 +25,7 @@ sleep	2
 host	echo "from_ns" | nc -N ::1 10000
 sleep	2
 host	echo
+sleep	1
 hout	NS_MSG cat /tmp/ns_msg
 check	[ __NS_MSG__ = "from_init" ]
 hostb	exit

test/distro/ubuntu

@@ -25,6 +25,7 @@ sleep	2
 host	echo "from_ns" | nc -q0 ::1 10000
 sleep	2
 host	echo
+sleep	1
 hout	NS_MSG cat /tmp/ns_msg
 check	[ __NS_MSG__ = "from_init" ]
 hostb	exit