Add logging to help users with encoding issues

We still haven't been able to get ontop of encoding issues in this app.
Most seem to happen when piping from stdout for which I am not clear
on the reasons. The logging information in this script may provide a
helpful prompt but a more permanent solution would be good.

src/demystify/demystify.py

@@ -267,6 +267,14 @@ def get_denylist_template() -> str:
 
 def main():
     """Primary entry point for Demystify from the command line."""
+    encoding = sys.stdout.encoding
+    logging.info(f"Console encoding: {encoding}")
+    if encoding != "utf-8":
+        logging.warning(f"Encoding '{encoding}' may result in the script failing")
+        logging.warning(
+            "Please try `set PYTHONIOENCODING=utf-8` (Windows) `export PYTHONIOENCODING=utf-8` (Linux)"
+        )
+
     parser = argparse.ArgumentParser(
         description="Analyse DROID and Siegfried results stored in a SQLite database"
     )