Install flux in container image

Dockerfile

 FROM alpine:3.13.5
 
 LABEL name="OpenAppStack management"
-LABEL version="4.2"
+LABEL version="4.3"
 LABEL vendor1="Greenhost"
 
 
 # Download yq v4 from github until it's packaged in alpine > 3.13
 ADD https://github.com/mikefarah/yq/releases/download/v4.7.0/yq_linux_amd64 /usr/local/bin/yq
+ADD https://github.com/fluxcd/flux2/releases/download/v0.15.0/flux_0.15.0_linux_amd64.tar.gz /tmp
+RUN tar -xzf /tmp/flux*.tar.gz && mv ./flux /usr/local/bin
 COPY ./test/pytest/le-staging-bundle.pem /usr/local/share/ca-certificates/le-staging-bundle.pem
 COPY ./requirements.txt /requirements.txt
 RUN \