feat(chart): Add the ability to mount the supergraph schema

[toneill818]

Added the ability to mount a supergraph with a configmap. If supergraphFile it will create a configmap named router-supergraph. It will also mount the supergraph and pass in the --supergraph option in the command line arguments. This makes it easy to use helm's set-file option to load a supergraph.

Example: helm upgrade --install --set-file supergraphFile supergraph.graphql [RELEASE_NAME] oci://ghcr.io/apollographql/helm-charts/router This command will set the value of supergraphFile the contents of supergraph.graphql and when the pod gets created it will mount the configmap and load the supergraph's schema.

[apollo-cla]

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[garypen]

Hi @toneill818. Thanks for submitting this PR. I've thought about it a little and I think this is worthwhile enhancement, but I'd like to tweak it a little bit so that it makes use of existing chart volume mount capabilities rather than modifying the deployment template.

The tweak is in PR: #2119 Let me know what you think.

[toneill818]

@garypen That looks good to me. Closing this PR in favor of PR #2119.