fix(aurora): fixed a dangerous-default-value pylint warning in database.mysql_log()

aurora/utilities/database.py

@@ -8,7 +8,8 @@ from discord import Guild
 from redbot.core import data_manager
 
 from .logger import logger
-from .utils import convert_timedelta_to_str, generate_dict, get_next_case_number
+from .utils import (convert_timedelta_to_str, generate_dict,
+                    get_next_case_number)
 
 
 def connect() -> sqlite3.Connection:
@@ -118,9 +119,9 @@ async def mysql_log(
     resolved_by: str = None,
     resolved_reason: str = None,
     expired: bool = None,
-    changes: list = [],
-    metadata: dict = {},
-) -> int: # pylint: disable=dangerous-default-value
+    changes: list = None,
+    metadata: dict = None,
+) -> int:
     if not timestamp:
         timestamp = int(time.time())
 
@@ -169,8 +170,8 @@ async def mysql_log(
         resolved_by,
         resolved_reason,
         expired,
-        json.dumps(changes),
-        json.dumps(metadata),
+        json.dumps(changes if changes else []),
+        json.dumps(metadata if metadata else {}),
     )
     cursor.execute(sql, val)