docs: fix enum docstring

Author: gsprochette

src/pruna/engine/load_artifacts.py

@@ -105,6 +105,9 @@ class LOAD_ARTIFACTS_FUNCTIONS(Enum):  # noqa: N801
         The type of the enum.
     start : int
         The start index for auto-numbering enum values.
+    boundary : enum.FlagBoundary or None
+        Boundary handling mode used by the Enum functional API for Flag and
+        IntFlag enums.
 
     Examples
     --------

src/pruna/engine/save_artifacts.py

@@ -110,6 +110,9 @@ class SAVE_ARTIFACTS_FUNCTIONS(Enum):  # noqa: N801
         The type of the enum.
     start : int
         The start index for auto-numbering enum values.
+    boundary : enum.FlagBoundary or None
+        Boundary handling mode used by the Enum functional API for Flag and
+        IntFlag enums.
 
     Examples
     --------