Add artifact uses

Author: etpeterson

.github/workflows/analysis.yml

@@ -51,6 +51,7 @@ jobs:
       - name: Generate figures
         run: Rscript --vanilla tests/IVIMmodels/unit_tests/analyze.r test_output.csv test_duration.csv
       - name: Upload figures
+        uses: actions/upload-artifact@v3
         with:
             name: code-coverage-report
             path: |