Correct the output_shape dimension for add_slice

Author: apbose

py/torch_tensorrt/fx/converters/operator.py

@@ -1208,7 +1208,7 @@ def add_slice(network, target, kwargs, name):
     stride = [1] * len(start)
     stride[dim] = step_int
     output_shape = list(input_val.shape)
-    output_shape[dim] = math.ceil((stop_int - start_int) // step_int)
+    output_shape[dim] = math.ceil((stop_int - start_int) / step_int)
 
     if dynamic_shape > 0:
         output_shape = get_shape_with_dynamic_shape(