[FRONTEND] interleave does not need to check shape (#4535)

1. Fixed the errors in the formulas in the comments.
2. When assert is enabled in DEBUG mode, using the list type will report
an error. Additionally, the Tensor returned by the internal interface
can ensure that the shape is a list and does not require checking.


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Co-authored-by: 谢双镱 <xieshuangyi@bytedance.com>

python/triton/language/standard.py

@@ -433,7 +433,7 @@ def flip(x, dim=None):
 def interleave(a, b):
     """
     Interleaves the values of two tensors along their last dimension. The two tensors must have the same shape.
-    Equivalent to `tl.join(a, b).reshape(a.shape[-1:] + [2 * a.shape[-1]])`
+    Equivalent to `tl.join(a, b).reshape(a.shape[:-1] + [2 * a.shape[-1]])`
 
     :param a: The first input tensor.
     :type a: Tensor
@@ -442,7 +442,6 @@ def interleave(a, b):
     """
     c = core.join(a, b)
 
-    assert isinstance(c.shape, list)
     if len(c.shape) == 1:
         # We must have interleaved two scalars.
         return c