debugging UX: load mainnet pool state in Go test

[p0mvn]

Background

It would be great to write all mainnet pool state into a json file and build out a test suite that loads all these pools into a Go test for debugging.

Acceptance Criteria

• Create a query to output all pool state into a local JSON file (this is not much).
• Disable this query from regular binary with build tags
• Create apptesting helper that reads a repository-local json file and outputs actual pools
• Consider some automation for updating this pool file

[p0mvn]

We can use osmosisd q poolmanager all-pools --output json > pools.json to get the pools into a file