[FRONTEND][Tensorflow] - Error for strided_slice after shape_of

When the Tensorflow Frontend of TVM handles the strided_slice op after shape_of, the special routine to handle the strided_slice op after shape_of may generate bugs under certain circumstances.

These bugs happen because the special routine may incorrectly conclude that the out_data is static.

This can be reproduced by this :

def slice_lab():
    debug_graph = tf.Graph()
    with debug_graph.as_default():
        t = tf.placeholder(dtype=tf.float32, shape=(None, None), name='input')
        s1 = tf.shape(t)
        st2 = tf.strided_slice(s1, [1], [2], [1], name='st2')

    mod, params = relay.frontend.from_tensorflow(
        debug_graph.as_graph_def(), 
        layout='NCHW', 
        outputs=['st2']
    )
    print(mod['main'])

The output logs, which is clearly wrong:

fn () -> Tensor[(0), int32] {
  meta[relay.Constant][0] /* ty=Tensor[(0), int32] */
}