Adding example on how to enable image-automation-controller through Bicep

[alexeybuzdin-aheads]

As mentioned #5 and https://docs.microsoft.com/en-us/answers/questions/930910/aks-flux-extension-imageupdateautomation-support.html it's a bit complicated to understand from documentation on how to enable https://docs.microsoft.com/en-us/azure/azure-arc/kubernetes/tutorial-use-gitops-flux2#control-which-controllers-are-deployed-with-the-flux-cluster-extension in Bicep.

This PR will not add additional value for the Proof of Concept but would help to understand on how to configure Azure Flux for production usage

[ghost]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

❌ alexeybuzdin-aheads sign now
_{You have signed the CLA already but the status is still pending? Let us recheck it.}