made argocd CM url override

Summary

This MR is to allow users of bigbang's argocd package the ability to set the url value for the argocd-cm configMap. Currently, the url value is hardcoded to https://argocd.{{ .Values.hostname }} and PB implementations of argocd need urls of argocd-il2.admin.dso.mil, argocd-il4.admin.dso.mil and argocd-il5.admin.dso.mil. This MR is to remove that setting in chart/templates/argocd/argocd-helmrelease.yaml and allow\force users to define their own value for the url.

Relevant logs/screenshots

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/cc @someoneelse