fix 1138 forcing cryptography version 2.5 or higher

Some fixing in devops-stages/stage-build
Use US18.04 for Dockerfile used for devops-stages

Change-Id: Ia2cb09e21efe11a22013de48b2404f5ead949a71
Signed-off-by: tierno <alfonso.tiernosepulveda@telefonica.com>
diff --git a/test-docker/test-gen-devops.sh b/test-docker/test-gen-devops.sh
index a869031..3b85166 100755
--- a/test-docker/test-gen-devops.sh
+++ b/test-docker/test-gen-devops.sh
@@ -26,7 +26,7 @@
   --no-cache    Use if found problems looking for packages
   --update      Use to update OSM, RO docker with this image" && exit 0
 
-[[ "$*" == *--no-cache* ]] && no_cache="--no_cache" || no_cache=""
+[[ "$*" == *--no-cache* ]] && no_cache="--no-cache" || no_cache=""
 [[ "$*" == *--update* ]] && update_osm="k8s" || update_osm=""
 
 HERE=$(dirname $(readlink -f ${BASH_SOURCE[0]}))