chore(deps): pin pydantic < 2 (#779)

## Change Summary

closes #778

## Checklist

- [ ] Unit tests for the changes exist
- [ ] Tests pass without significant drop in coverage
- [ ] Documentation reflects changes where applicable
- [ ] Test snapshots have been
[updated](https://prisma-client-py.readthedocs.io/en/latest/contributing/contributing/#snapshot-tests)
if applicable

## Agreement

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requirements/base.txt

@@ -1,6 +1,6 @@
 httpx>=0.19.0
 jinja2>=2.11.2
-pydantic>=1.8.0
+pydantic>=1.8.0, < 2.0.0
 click>=7.1.2
 python-dotenv>=0.12.0
 typing-extensions>=4.0.1