prodimage: add gnpug, use pl mirrors

Change-Id: I6245e9b1b127c5db574d58e35b5f3006551d795b
diff --git a/devtools/prodimage/Dockerfile b/devtools/prodimage/Dockerfile
index 8603463..cb5e7db 100644
--- a/devtools/prodimage/Dockerfile
+++ b/devtools/prodimage/Dockerfile
@@ -1,10 +1,14 @@
 FROM ubuntu:bionic-20190515
 
 RUN set -e -x ;\
+    sed -i 's/archive/pl.archive/' /etc/apt/sources.list
+
+RUN set -e -x ;\
     export DEBIAN_FRONTEND=noninteractive ;\
     apt-get -y update ;\
     apt-get -y install \
         ca-certificates \
+        gnupg2 \
         rsync \
         python \
         python3 ;\