Logs and metrics for unsupported methods

[acuarica]

As a follow up of #2613, we should include a mechanism to detect whether users are trying to use unsupported methods. In particular, we should include logs (if not included yet) and metrics/dashboards to visualize which valid unsupported methods users are trying to invoke.

Here valid means any method supported by either the Ethereum spec or a method that is widely accepted by the community.