fix: Pin pydantic to >=2.x

[jeffkinnison]

We pinned pydantic to 1.x in #3537 to resolve an incompatibility with transformers. #3834 pinned huggingface-hub to 0.19, which requires pydantic` 2.x. This PR is to resolve this and any other dependency issues.

[github-actions]

Unit Test Results

    6 files  ±    0      6 suites  ±0   11m 50s ⏱️ - 2m 17s
  60 tests +  48    45 ✔️ +36    7 💤 +4    8 ❌ +  8 
180 runs  +120  135 ✔️ +93  21 💤 +3  24 ❌ +24 

For more details on these failures, see this check.

Results for commit b2320a2. ± Comparison against base commit 7e8fc14.