:sparkles: add fact checking command

[Chippers255]

Summary

What's this nonsense? Added a new !truth command that lets users summon the almighty DuckBot to fact-check Discord messages. Because who doesn't love being told they're wrong by a robot?

Why though? Because misinformation is so 2020, and we're all about that fact-checking life now.

Checklist

• [x] this is a source code change
  • [x] run format in the repository root
  • [x] run pytest in the repository root
  • [ ] link to issue being fixed using a fixes keyword, if such an issue exists
  • [x] update the wiki documentation if necessary
• [ ] or, this is not a source code change

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 96.43%. Comparing base (3de213d) to head (eb17bef). Report is 1 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #979 +/- ## ========================================== + Coverage 96.37% 96.43% +0.05% ========================================== Files 92 94 +2 Lines 2152 2187 +35 Branches 153 155 +2 ========================================== + Hits 2074 2109 +35 Misses 67 67 Partials 11 11 ```

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