don't slice shape if shape size<=1 of sparsegatherv2 grad

mindspore/ops/_grad/grad_array_ops.py

@@ -433,7 +433,10 @@ def get_bprop_sparse_gather_v2(self):
         x_shp = shape_op(x)
         if axis == 0:
             indices_size = (size_op(indices),)
-            x_tail_shp = x_shp[1:]
+            if len(x_shp) <= 1:
+                x_tail_shp = ()
+            else:
+                x_tail_shp = x_shp[1:]
             values_shape = indices_size + x_tail_shp
             values = reshape(dout, values_shape)
             indices_new = reshape(indices, indices_size)