Make explicit cross-version support for Pydantic

[cthoyt]

As a follow-up to biopragmatics/curies#64 (and related to #920 and #899), this PR makes Bioregistry support both Pydantic v1 and v2

[codecov]

Codecov Report

Patch coverage: 96.29% and project coverage change: +0.10% 🎉

Comparison is base (4c57b37) 40.84% compared to head (b13867b) 40.94%.
Report is 7 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #921      +/-   ##
==========================================
+ Coverage   40.84%   40.94%   +0.10%     
==========================================
  Files         135      135              
  Lines        7773     7788      +15     
  Branches     1808     1810       +2     
==========================================
+ Hits         3175     3189      +14     
- Misses       4399     4400       +1     
  Partials      199      199              

Files Changed	Coverage Δ
src/bioregistry/schema/struct.py	86.99% <95.00%> (+<0.01%)	⬆️
src/bioregistry/app/impl.py	80.76% <100.00%> (+0.24%)	⬆️
src/bioregistry/constants.py	100.00% <100.00%> (ø)
src/bioregistry/utils.py	67.18% <100.00%> (+1.05%)	⬆️

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.