take advantage of restart=always in tests

This should have been done as part of #2029.

test/310_docker_restart_test.sh

@@ -25,8 +25,8 @@ start_suite "Containers get same IP address on restart"
 # Remove any persisted data from previous runs
 run_on $HOST1 "sudo rm -f /tmp/test163-*"
 
-WEAVE_DOCKER_ARGS="-v /tmp:/db --restart=always" weave_on $HOST1 launch-router --db-prefix=/db/test163-
-WEAVEPROXY_DOCKER_ARGS=--restart=always weave_on $HOST1 launch-proxy
+WEAVE_DOCKER_ARGS="-v /tmp:/db" weave_on $HOST1 launch-router --db-prefix=/db/test163-
+weave_on $HOST1 launch-proxy
 
 # Use up first address with throwaway container
 start_container $HOST1 --name=c1

test/640_proxy_restart_reattaches_test.sh

@@ -33,7 +33,7 @@ run_many() {
 
 start_suite "Proxy restart reattaches networking to containers"
 
-WEAVE_DOCKER_ARGS=--restart=always WEAVEPROXY_DOCKER_ARGS=--restart=always weave_on $HOST1 launch
+weave_on $HOST1 launch
 proxy_start_container          $HOST1 -di --name=c2 --restart=always -h $NAME
 proxy_start_container_with_dns $HOST1 -di --name=c1 --restart=always
 C2=$(container_ip $HOST1 c2)