[Misc] Modify xgrammar version

[shen-shanshan]

What this PR does

As mentioned in this PR (#13894), xgrammar have supported aarch64 system.

After my test, the result showed that guided decoding worker well with xgrammar on aarch64 system.

So we should modify the xgrammar version in requirement.txt after merging this PR (#13894).

Find more details about xgrammar v0.1.14.

Part of test logs:

Processed prompts: 100%|█████████████████████████████████████████████████████████████████████████| 1/1 [00:01<00:00,  1.49s/it, est. speed input: 7.41 toks/s, output: 1.35 toks/s]
Positive
WARNING 02-28 09:29:50 [__init__.py:33] xgrammar does not support regex guided decoding. Falling back to use outlines instead.
('Warning: torch.save with "_use_new_zipfile_serialization = False" is not recommended for npu tensor, which may bring unexpected errors and hopefully set "_use_new_zipfile_serialization = True"', 'if it is necessary to use this, please convert the npu tensor to cpu tensor for saving')
Processed prompts: 100%|█████████████████████████████████████████████████████████████████████████| 1/1 [00:04<00:00,  4.21s/it, est. speed input: 7.59 toks/s, output: 1.90 toks/s]
alan_turing@enigma.com

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