1. Proposed title of this feature request
Support volume mounts in ArgoCD Server deployment

2. What is the nature and description of the request?

To be able to define custom styles in ArgoCD by mounting the CSS file to ArgoCD server and for UI extensions.
https://argo-cd.readthedocs.io/en/stable/operator-manual/custom-styles/

3. Why does the customer need this? (List the business requirements here)

4. List any affected packages or components.