fix: Revert of dup cherry-pick #1949 (#2088)

Signed-off-by: yangxuan <[email protected]>

pymilvus/orm/schema.py

@@ -277,14 +277,12 @@ def enable_dynamic_field(self, value: bool):
  self._enable_dynamic_field = bool(value)
 
  def to_dict(self):
- _dict = {
+ return {
  "auto_id": self.auto_id,
  "description": self._description,
  "fields": [s.to_dict() for s in self._fields],
+ "enable_dynamic_field": self.enable_dynamic_field,
  }
- if self._enable_dynamic_field is not None:
- _dict["enable_dynamic_field"] = self._enable_dynamic_field
- return _dict
 
  def verify(self):
  # final check, detect obvious problems