Fix check design.

workflow/tests/test_check_design.py

@@ -3,7 +3,7 @@
 import pytest
 import pandas as pd
 from io import StringIO
-from design_file import check_design
+import check_design
 
 
 DESIGN_STRING = """sample_id\texperiment_id\tbiosample\tfactor\ttreatment\treplicate\tfastq_read1