Update RUST_LOG from verbose to debug, as verbose outputs no logging

[Fmstrat]

When troubleshooting, verbose value for RUST_LOG doesn't print anything, not even info values. So if you're trying to figure out why your upgrade isn't loading in the UI, you turn on verbose logging but can't see that the DB migrations are running.

Updated the "most verbose" line in the Troubleshooting doc to use debug instead, which provides more context than info.

[Nutomic]

Its because verbose is not a valid log level, it should be trace instead. Can you change that?

https://docs.rs/env_logger/latest/env_logger/#enabling-logging