[oathkeeper] allow to add additional containers

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Describe your problem

Until ory/oathkeeper#969 is resolved, I need to add a proxy that will add authentication headers to the request to the authorization server. I would like to add a sidecar to oathkeeper chart so I could run Nginx (or any other proxy) that is capable of adding the authorization header before passing the request to upstream.

Describe your ideal solution

Adding something like .sidecar to the chart with full container spec so I could define additional containers on the chart. I will probably also need to mount volumes for Nginx config / authentication to the authorization credentials.

Workarounds or alternatives

Running the proxy as another deployment (insecure), fixing the original issue in oathkeeper or forking the chart.

Version

latest

Additional Context

No response

ory / k8s