Migrate lua based health assessment from Argo CD

[alexmt]

Summary

Argo CD provides a way to customize resources health assessment using the Lua script. The argocd repository contains library of Lua scripts as well as test framework that validates scripts: https://github.com/argoproj/argo-cd/tree/master/resource_customizations

Proposal

Migrate Lua scripts and testing infrastructure to the GitOps engine to make it available for everyone.

[sergeyshevch]

@alexmt I guess i can pick this. But there is some questions. Can you confirm my order of actions

1. Add all code from argo-cd/util/lua and argocd/recouse_customization to gitops engine package
2. Wait for review and merge of this PR
3. Replace usage of this package in argo-cd to gitops-engine and provide changes into doc.

Also small question about documenations. Currenct documentation notice that you need to contribute to argocd package. https://argoproj.github.io/argo-cd/operator-manual/health/#way-2-contribute-a-custom-health-check Am I righ that i need to replace it to gitops engine?