✨ expose init-shared-path readOnly var

[vmdude]

what

By default init-shared-path is read-only mounted without the possibility to mount it read-write. This PR expose the readOnly setting of the volumeMount to be able to manage it through values file.

why

We used to build a custom atlantis image to be able to embed additional tools required by custom workflows defined server-side (like aws-cli or asdf to handle terraform, terragrunt, opentofu, kubectl and others). Although it works just fine, we had to maintain our custom image.
Since initConfig object, we have been able to move the instruction from our custom Dockerfile to the initConfig.script value.
The main issue is that the initConfig.sharedDir is mounted read-write on the init container, but is mounted read-only on the main container.
As we're using asdf is all our repositories with sometimes different versions for each tool, the atlantis image is installing these different versions of terraform/opentofu/... during the pre_workflow_hooks thanks to a .tool-versions in each repository. But asdf require to download and install each version where it was installed (ie in the sharedDir), thus require read-write volumeMount.

Today we're using kustomize to patch it so that it's mounted correctly, but we're hoping this could be handled directly through the chart itself:

- op: replace
  path: /spec/template/spec/containers/0/volumeMounts/3/readOnly
  value: false

[GMartinez-Sisti]

Thanks @vmdude! Also please bump minor since this is a new feature and run the helm-docs update (instructions on the README file).

[vmdude]

Thanks for your feedback, I just pushed the required modification

[GMartinez-Sisti]

Thanks for the contribution 🙏