fix: add dart version to obs converter build functions

[hkershaw-brown]

Description:

This pull request adds the dart version to the obs convert build functions.
Following the buildfunctions for models interfaces (#983)

Fixes issue

fixes #1112

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Documentation changes needed?

• My change requires a change to the documentation.
  • I have updated the documentation accordingly.

Tests

Please describe any tests you ran to verify your changes.
Build and run WOD converter.
Ran all quickbuilds (https://github.com/NCAR/DART/actions/runs/26180325584) to check all converter builds.

Checklist for merging

• Updated changelog entry
• Documentation updated
• Update conf.py

Checklist for release

• Merge into main
• Create release from the main branch with appropriate tag
• Delete feature-branch

Testing Datasets

• Dataset needed for testing available upon request
• Dataset download instructions included
• No dataset needed

[mjs2369]

Ready to merge