fix(wlasl): add missing attribute

wlasl.py

@@ -55,6 +55,7 @@ class WLASL(datasets.GeneratorBasedBuilder):
             "fps": datasets.Value("int8"),
             "frame_end": datasets.Value("int32"),
             "frame_start": datasets.Value("int32"),
+            "instance_id": datasets.Value("int32"),
             "signer_id": datasets.Value("int32"),
             "source": datasets.Value("string"),
             "url": datasets.Value("string"),