CompatHelper: bump compat for OrdinaryDiffEqCore to 2, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the OrdinaryDiffEqCore package from 1 to 1, 2.
This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry.
It is your responsibility to make sure that your package tests pass before you merge this pull request.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.81%. Comparing base (2ff8980) to head (8ba41b6).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #219      +/-   ##
==========================================
+ Coverage   93.36%   94.81%   +1.44%     
==========================================
  Files          25       25              
  Lines        1523     1523              
==========================================
+ Hits         1422     1444      +22     
+ Misses        101       79      -22     

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

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.