Add tests for app/print_table.py (#15)

* Add tests for app/print_table.py

* Exclude app/version and app/args from coverage

* Remove app/main from coverage (just uses other modules)

app/print_table.py

@@ -18,6 +18,6 @@ def generate_prefix_string(prefixes: list) -> Union[str, None]:
         return None
 
 
-def print_table(table_data) -> None:
+def print_table(table_data) -> None:  # pragma: no cover
     """Print table generated by tabulate."""
     print(tabulate(table_data))