test pydantic v2

[codecov[bot]]

Codecov Report

Patch and project coverage have no change.

Comparison is base (0b611a5) 99.12% compared to head (e050553) 99.12%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #226 +/- ## ======================================= Coverage 99.12% 99.12% ======================================= Files 36 36 Lines 1831 1838 +7 ======================================= + Hits 1815 1822 +7 Misses 16 16 ``` [see 4 files with indirect coverage changes](https://app.codecov.io/gh/OpenFreeEnergy/gufe/pull/226/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=OpenFreeEnergy)

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[mikemhenry]

Like https://github.com/OpenFreeEnergy/openfe/pull/541 should I add another CI job to the matrix that checks to make sure things work with the older version of pydantic?

[richardjgowers]

@mikemhenry yup