Migrate to grafana-create plugin

[cnoelle]

https://grafana.com/developers/plugin-tools/migration-guides/migrate-from-toolkit

[cnoelle]

See also:
https://grafana.com/developers/plugin-tools/publish-a-plugin/package-a-plugin
https://grafana.com/developers/plugin-tools/publish-a-plugin/publish-a-plugin

[cnoelle]

Blocked by missing Windows support of the create plugin:
grafana/plugin-tools@8d3433b
https://grafana.com/developers/plugin-tools/troubleshooting#i-am-getting-unsupported-operating-system-windows-detected-please-use-wsl-with-create-plugin