Fix typo in explode_env_vars() docstring (#207)

Author: paytonward6

pydantic_settings/sources.py

@@ -515,7 +515,7 @@ def explode_env_vars(self, field_name: str, field: FieldInfo, env_vars: Mapping[
             env_vars: Environment variables.
 
         Returns:
-            A dictionaty contains extracted values from nested env values.
+            A dictionary contains extracted values from nested env values.
         """
         prefixes = [
             f'{env_name}{self.env_nested_delimiter}' for _, env_name, _ in self._extract_field_info(field, field_name)