[Fix] Fix the potential NaN bug in calc_square_dist()

[ZCMax]

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Motivation

The result of calc_square_dist() function could beNaN according to the issue #2178.

Modification

We directly use torch.cdist to calculate the square distance instead.

BC-breaking (Optional)

Does the modification introduce changes that break the backward-compatibility of the downstream repositories?
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Use cases (Optional)

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Checklist

Before PR:

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• Bug fixes are covered by unit tests, the case that causes the bug should be added in the unit tests.
• New functionalities are covered by complete unit tests. If not, please add more unit test to ensure the correctness.
• The documentation has been modified accordingly, including docstring or example tutorials.

After PR:

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