fixed connecting with empty mysql password (#128)

null password was being converted by str() into a literal string "None"

Author: mackuba

src/sqlite3_to_mysql/transporter.py

@@ -69,7 +69,7 @@ def __init__(self, **kwargs: tx.Unpack[SQLite3toMySQLParams]):
         else:
             raise ValueError("Please provide a MySQL user")
 
-        self._mysql_password = str(kwargs.get("mysql_password")) or None
+        self._mysql_password = str(kwargs.get("mysql_password")) if kwargs.get("mysql_password") else None
 
         self._mysql_host = str(kwargs.get("mysql_host", "localhost"))