chore(deps): drop Pydantic dependency

[tigarmo]

We don't use the library at all - probably what happened is that we copied the deps from somewhere else.

Fixes #201

• [ ] Have you followed the guidelines for contributing?
• [ ] Have you signed the CLA?
• [ ] Have you successfully run tox?

[codecov[bot]]

Codecov Report

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

Comparison is base (8332b8f) 94.76% compared to head (1e6ac81) 94.76%. Report is 1 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #207 +/- ## ======================================= Coverage 94.76% 94.76% ======================================= Files 7 7 Lines 1070 1070 Branches 197 197 ======================================= Hits 1014 1014 Misses 53 53 Partials 3 3 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.