Add default troubleshooting template for missing exchange rates

[zachgoll]

Currently, the account sync process is fully setup to capture warnings and errors encountered when attempting to sync account balances and holdings.

We currently have a placeholder "troubleshooting" guide for all errors encountered.

This issue will tackle the first and most common error during the Sync process, which involves:

• Exchange rate provider not connected properly
• Exchange rates missing
• Not enough API credits to sync exchange rates

The goal here is to build a "template" for extending this into the future so we can easily:

1. Catch sync errors
2. Report these errors to the user
3. Write a concise troubleshooting guide for the error