add ability to call json_loader with a Path object

[sierra-moxon]

fixes linkml issue #2458

[codecov]

Codecov Report

Attention: Patch coverage is 71.42857% with 4 lines in your changes missing coverage. Please review.

Project coverage is 63.46%. Comparing base (1b5e9f7) to head (f1625ad).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
linkml_runtime/loaders/json_loader.py	66.66%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #354      +/-   ##
==========================================
+ Coverage   63.43%   63.46%   +0.02%     
==========================================
  Files          63       63              
  Lines        8982     8994      +12     
  Branches     2574     2577       +3     
==========================================
+ Hits         5698     5708      +10     
- Misses       2665     2668       +3     
+ Partials      619      618       -1     

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