Fix guard both OptionalImportError raises with raise_on_missing_reader flag

Both raise statements in LoadImage.__init__ now use the same guarding
mechanism via the raise_on_missing_reader flag. This ensures consistent
behavior when dealing with missing readers whether they are unrecognized
names or missing optional dependencies.

Also applied code formatting fixes.

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

Author: its-serah

monai/transforms/io/array.py

@@ -214,9 +214,16 @@ def __init__(
                         the_reader = look_up_option(_r.lower(), SUPPORTED_READERS)
                     except ValueError:
                         # If the reader name is not recognized at all, raise OptionalImportError
-                        raise OptionalImportError(
-                            f"Cannot find reader '{_r}'. It may not be installed or recognized."
-                        )
+                        if self.raise_on_missing_reader:
+                            raise OptionalImportError(
+                                f"Cannot find reader '{_r}'. It may not be installed or recognized."
+                            )
+                        else:
+                            warnings.warn(
+                                f"Cannot find reader '{_r}'. It may not be installed or recognized. "
+                                f"Will use fallback readers if available."
+                            )
+                            continue
                 try:
                     self.register(the_reader(*args, **kwargs))
                 except OptionalImportError as e: