Issue 1910: Do not impute income for 0 population tracts (#1918)

* should be working, has unnecessary loggers

* removing loggers and cleaning up

* updating ejscreen tests

* adding tests and responding to PR feedback

* fixing broken smoke test

* delete smoketest docs

data/data-pipeline/data_pipeline/etl/base.py

@@ -365,6 +365,9 @@ class ExtractTransformLoad:
                 f"No file found at `{output_file_path}`."
             )
 
+        logger.info(
+            f"Reading in CSV `{output_file_path}` for ETL of class `{cls}`."
+        )
         output_df = pd.read_csv(
             output_file_path,
             dtype={