chore: drop unnecessary | None on LLMError and Mail.send (#36147)

Co-authored-by: Brian Wang <20699847+BrianWang1990@users.noreply.github.com>

api/core/errors/error.py

@@ -1,9 +1,9 @@
 class LLMError(ValueError):
     """Base class for all LLM exceptions."""
 
-    description: str | None = None
+    description: str = ""
 
-    def __init__(self, description: str | None = None):
+    def __init__(self, description: str = ""):
         self.description = description
 
 

api/extensions/ext_mail.py

@@ -67,7 +67,7 @@ class Mail:
             case _:
                 raise ValueError(f"Unsupported mail type {mail_type}")
 
-    def send(self, to: str, subject: str, html: str, from_: str | None = None):
+    def send(self, to: str, subject: str, html: str, from_: str = ""):
         if not self._client:
             raise ValueError("Mail client is not initialized")