🏷️ cast parsed SQL expressions to the correct type for type safety

Author: techouse

src/sqlite3_to_mysql/transporter.py

@@ -389,7 +389,7 @@ def _parse_sql_expression(value: str) -> t.Optional[exp.Expression]:
             return None
         for dialect in ("mysql", "sqlite"):
             try:
-                return sqlglot.parse_one(stripped, read=dialect)
+                return t.cast(exp.Expression, sqlglot.parse_one(stripped, read=dialect))
             except sqlglot_errors.ParseError:
                 continue
         return None