create secret in argocd and remove secret values from authservice configmap

[mathis-marcotte]

Relates to https://github.com/StatCan/aaw-private/issues/149

update the manifest for oidc-authservice so that we actually start using the secret object that gets created from upstream, and link that k8s secret to the AKV secret with the help of the azure vault plugin

We will also need to remove the client_id and client_secret from the config map to make the oidc_authservice read the values from the secret instead (it is already referenced in the statefulset of the application)

(I already started in a branch but I only wrote what I think the secret will be. This is untested since we would need the argocd-vault-plugin first installed)