Feature 10509 manual scaling for native K8s charm

This robot test created for this specific package
https://osm.etsi.org/gitlab/vnf-onboarding/osm-packages/-/merge_requests/154
Test case steps:
1 - Adds packages
2 - Adds K8s Cluster
3 - Creates NS Service
4 - Gets the scale count
5 - Scale-out the NS
6 - Checks scale count
7 - Scale-in the NS
8 - Check scale count
9 - Removes the NS, K8s cluster and packages
This commit includes Juju support

Change-Id: Iba7c59a65c9ae2607b23c7104e8178e20b502c60
Signed-off-by: aktas <emin.aktas@ulakhaberlesme.com.tr>
(cherry picked from commit f47542be165ebd69b91945041697181b4df63954)
diff --git a/docker/Dockerfile b/docker/Dockerfile
index 0431642..cc484bd 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -21,6 +21,17 @@
 RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get -y install git software-properties-common \
     make python3 debhelper python3-pip apt-utils ssh iputils-ping libcurl4-openssl-dev libssl-dev cargo rustc
 
+# Installing Juju
+ARG JUJU_VERSION_M=2.8
+ARG JUJU_VERSION_R=11
+ARG JUJU_VERSION=$JUJU_VERSION_M.$JUJU_VERSION_R
+
+RUN curl --output /tmp/juju-$JUJU_VERSION-linux-amd64.tar.xz -LO \
+    https://launchpad.net/juju/$JUJU_VERSION_M/$JUJU_VERSION/+download/juju-$JUJU_VERSION-linux-amd64.tar.xz && \
+    tar -xf /tmp/juju-$JUJU_VERSION-linux-amd64.tar.xz -C /tmp && \
+    install /tmp/juju /usr/local/bin/juju && \
+    rm /tmp/juju /tmp/juju-$JUJU_VERSION-linux-amd64.tar.xz
+
 RUN add-apt-repository -y ppa:rmescandon/yq && apt update && apt install yq -y 
 
 RUN python3 -m pip install -U pip
@@ -56,6 +67,9 @@
 # Kubeconfig file
 ENV K8S_CREDENTIALS=/root/.kube/config
 
+# Juju data folder
+ENV JUJU_DATA=/root/.local/share/juju
+
 ENV LC_ALL=C.UTF-8
 ENV LANG=C.UTF-8