[appmesh-prometheus] Remote Write

**Is your feature request related to a problem?**
Please extend the appmesh-prometheus chart to include the ability to configure a remote-write option. This would enable users to send their envoy metrics to a visualization database of their own choosing

**Is your feature request related to a specific Helm chart, if yes mention name of the chart?**
appmesh-prometheus

**Describe the solution you'd like**
Create a value that allows the user to enable and configure the remote-write option

Locate the appmesh-prometheus Helm chart and inspect its existing values and templates for configurable Prometheus behavior. Add the requested enable/configuration setting for remote write, then verify the rendered chart reflects the option and preserves the existing defaults.

Written by the indexing model from the issue text.