feat(mge): do not export F.nn.nms

GitOrigin-RevId: 7a0a328c37ff45d10e75a9880a35a03ddbd96a44

imperative/python/megengine/functional/nn.py

@@ -43,7 +43,6 @@ __all__ = [
     "logsoftmax",
     "matmul",
     "max_pool2d",
-    "nms",
     "one_hot",
     "prelu",
     "roi_align",
@@ -1482,7 +1481,7 @@ def nms(boxes: Tensor, scores: Tensor, iou_thresh: float) -> Tensor:
         x[:,2:] = np.random.rand(100,2)*20 + 100
         scores = tensor(np.random.rand(100))
         inp = tensor(x)
-        result = F.nms(inp, scores, iou_thresh=0.7)
+        result = F.nn.nms(inp, scores, iou_thresh=0.7)
         print(result.numpy())
 
     Outputs:

imperative/python/test/unit/functional/test_functional.py

@@ -357,7 +357,7 @@ def test_nms():
     )
     inp = tensor(x)
     scores = tensor([0.5, 0.8, 0.9, 0.6], dtype=np.float32)
-    result = F.nms(inp, scores=scores, iou_thresh=0.5)
+    result = F.nn.nms(inp, scores=scores, iou_thresh=0.5)
     np.testing.assert_equal(result.numpy(), np.array([2, 1, 3], dtype=np.int32))