fix linting

Author: Jingjing Tang

changehc/delphi_changehc/load_data.py

@@ -95,7 +95,7 @@ def load_combined_data(denom_filepath, covid_filepath, base_geo,
     issue_date = datetime.strptime(covid_filepath.split("/")[-1][:8], "%Y%m%d")
     assert (
         issue_date == datetime.strptime(denom_filepath.split("/")[-1][:8], "%Y%m%d")
-    ), "The aggregated files used for Covid Claims and Total Claims should have the same drop date." 
+    ), "The aggregated files used for Covid Claims and Total Claims should have the same drop date."
 
     # load each data stream
     denom_data = load_chng_data(denom_filepath, issue_date, base_geo,