Feature Request: Add PostgreSQL dashboard template

[kassiansun]

Is your feature request related to a problem? Please describe.
Due to the unique syntax of tencloud API, it's hard to build a comprehensive panel/dashboard for PostgreSQL from scratch

Describe the solution you'd like
It would be better to get a default one and copy-paste-modify it.

Describe alternatives you've considered
Tried to copy MongoDB dashboard, the panel query has auto-completion, but the variables are hard to modify.

Additional context
Add any other context or screenshots about the feature request here.