Fix stage3 issues: obsolete k8s deb packages and mongodb charm version

The change updates LCM Dockerfile and OSM installer to use Kubernetes
version 1.28 instead of 1.26.

In addition, mongodb is installed from 6/stable channel instead of
latest/stable

Change-Id: Ib67654765ddec0990af70404f7f8a7fff68bd1ef
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>

docker/LCM/Dockerfile

@@ -42,9 +42,9 @@ RUN DEBIAN_FRONTEND=noninteractive apt-get --yes update && \
     && rm -rf /var/lib/apt/lists/*
 
 # https://kubernetes.io/releases/
-RUN curl -fsSL https://pkgs.k8s.io/core:/stable:/v1.26/deb/Release.key | gpg --dearmor -o /etc/apt/keyrings/kubernetes-apt-keyring.gpg \
-    && echo 'deb [signed-by=/etc/apt/keyrings/kubernetes-apt-keyring.gpg] https://pkgs.k8s.io/core:/stable:/v1.26/deb/ /' | tee /etc/apt/sources.list.d/kubernetes.list \
-    && apt-get update && apt-get install -y kubectl=1.26.14-1.1
+RUN curl -fsSL https://pkgs.k8s.io/core:/stable:/v1.28/deb/Release.key | gpg --dearmor -o /etc/apt/keyrings/kubernetes-apt-keyring.gpg \
+    && echo 'deb [signed-by=/etc/apt/keyrings/kubernetes-apt-keyring.gpg] https://pkgs.k8s.io/core:/stable:/v1.28/deb/ /' | tee /etc/apt/sources.list.d/kubernetes.list \
+    && apt-get update && apt-get install -y kubectl=1.28.2-1.1
 
 RUN curl https://get.helm.sh/helm-v2.17.0-linux-amd64.tar.gz --output helm-v2.17.0.tar.gz \
     && tar -zxvf helm-v2.17.0.tar.gz \

installers/install_kubeadm_cluster.sh

@@ -15,8 +15,8 @@
 
 set +eux
 
-K8S_VERSION=1.26
-K8S_PACKAGE_VERSION="$K8S_VERSION".15-1.1
+K8S_VERSION=1.28
+K8S_PACKAGE_VERSION="$K8S_VERSION".2-1.1
 
 # installs kubernetes packages
 function install_kube() {