make ReadWriteMany the default accessMode

with this MR, I am making ReadWriteMany to the default accessmode as we have a new storage cluster now

merged

assigned to @philipp.sommer

enabled an automatic merge when the pipeline for 46f91f40 succeeds

mentioned in commit 0b139802

mentioned in commit hcdc/kubernetes/charts/postgres@c2794b71

mentioned in commit hcdc/kubernetes/charts/django@c7a7be45

mentioned in merge request hcdc/kubernetes/charts/django!2 (merged)