Add support for darwin arm64 when installing the plugin via Grafana CLI

[MissingRoberto]

What would you like to be added:

Add support for darwin-arm64 when installing the plugin.

Why is this needed:

If you follow the official documentation of this plugin the recommended installation path is by running grafana-cli plugins install grafana-image-renderer which doesn't work on new macbooks.

 grafana-cli --homepath $(pwd) --pluginsDir $(pwd)/data/plugins plugins install grafana-image-renderer
Deprecation warning: The standalone 'grafana-cli' program is deprecated and will be removed in the future. Please update all uses of 'grafana-cli' to 'grafana cli'
Error: ✗ [plugin.archNotFound] grafana-image-renderer is not compatible with your system architecture: darwin-arm64

The first Apple Silicon macbooks were released in 2020, which means that most people using macbooks currently will have one of those and will hit this issue if they try to install this plugin.

Official documentation: https://grafana.com/grafana/plugins/grafana-image-renderer/?tab=installation#installation

The original request for this can be found in #7 but it forces you to run Grafana using Docker and it does not support running things locally which is the recommended way for contributors and provide hot reload for quick development.