Move default Redis connection string out of CD spec into secret

[robhabraken]

The Kubernetes specification files as provided contain a hard-coded connection string to Redis. You can of course change it in there (the cd.yaml spec file in your repo), but I think it is more elegant to remove the value from the specification files and place it inside a secrets file, as is being done with the Solr connection string. This makes the spec file implementation-agnostic, easier to upgrade and not containing environment specific variables / parameters. Subsequently, you can choose to retrieve this connection string value either from an Azure DevOps Variable group, or by using a secret from your Azure KeyVault instance for example, to inject the correct value in the secrets file at provisioning-time.

I also mentioned this in my blog post https://www.robhabraken.nl/index.php/3619/paas-to-aks-arm-for-eds/, this is the corresponding Pull Request of said change to the spec files.

[robhabraken]

Thanks Jonas! I only saw this remark in the README after submitting my PR. Thanks for evaluating my proposal and looking forward to a contrib branch!

[bplasmeijer]

@michaelbaranov can you share with the container team.