run diff for -ref branch run and only save output data artifacts if t…

…here are differences -- this should only update the truth data for use case groups that need to be updated

.github/jobs/set_job_controls.sh

@@ -33,6 +33,7 @@ elif [ "${GITHUB_EVENT_NAME}" == "workflow_dispatch" ]; then
 elif [ "${GITHUB_REF: -4}" == -ref ]; then
   run_all_use_cases=true
   run_save_truth_data=true
+  run_diff=true
 # if not pull request or -ref branch, apply commit messages overrides
 else
 

.github/workflows/testing.yml

@@ -205,12 +205,12 @@ jobs:
       # copy output data to save as artifact
       - name: Save output data
         id: save-output
-        if: ${{ always() && steps.run_tests.conclusion != 'skipped' }}
+        if: ${{ always() && steps.run_tests.conclusion != 'skipped' && (!endsWith(needs.job_control.outputs.branch_name, '-ref') || steps.run-diff.conclusion == 'failure') }}
         run: .github/jobs/copy_output_to_artifact.sh ${{ steps.get-artifact-name.outputs.artifact_name }}
 
       - name: Upload output data artifact
         uses: actions/upload-artifact@v3
-        if: ${{ always() && steps.run_tests.conclusion != 'skipped' }}
+        if: ${{ always() && steps.run_tests.conclusion != 'skipped' && (!endsWith(needs.job_control.outputs.branch_name, '-ref') || steps.run-diff.conclusion == 'failure') }}
         with:
           name: ${{ steps.get-artifact-name.outputs.artifact_name }}
           path: artifact/${{ steps.get-artifact-name.outputs.artifact_name }}