Run full test suite on schedule build (#103)

Mic-4380/Run full test suite on schedule build

Mic-4380/Run full test suite on schedule build
- *Category*: CI
- *JIRA issue*: [MIC-4380](https://jira.ihme.washington.edu/browse/MIC-4380)
- *Research reference*: <!--Link to research documentation for code -->

Changes and notes
-Run full test suite on schedule build

Verification and Testing

.github/workflows/build.yml

@@ -39,7 +39,11 @@ jobs:
           isort . --check --verbose --only-modified --diff
       - name: Test
         run: |
-          pytest ./tests
+          if github.event_name == 'schedule'; then
+            pytest --runslow ./tests
+          else
+            pytest ./tests
+          fi
       - name: Doc build
         run: |
           make html -C docs/ SPHINXOPTS="-W --keep-going -n"