Broken "Skymath" link in README.md (malformed markdown + wrong URL)

[pavansai018]

In README.md, the sentence pointing to the SkyMath paper has a malformed link:

...please refer to our [technical report](http://arxiv.org/abs/2310.19341),
[Skymath]((https://arxiv.org/skywork-tech-report)) paper and
[SkyworkMM](...) paper.

Two issues:

1. The link destination is wrapped in double parentheses
   ((https://arxiv.org/skywork-tech-report)) instead of single
   (https://arxiv.org/skywork-tech-report). This breaks markdown
   link parsing — verified against GitHub's own markdown rendering
   API, which renders "Skymath" as plain, unlinked text instead of
   a hyperlink, unlike "technical report" and "SkyworkMM" right next
   to it in the same sentence.

2. Even if the parenthesis were fixed, the URL itself
   (arxiv.org/skywork-tech-report) isn't a valid arXiv path —
   arXiv URLs follow the arxiv.org/abs/<id> format. The correct
   ID for this paper is already given later in the same README, in
   the bibtex citation block:

   @article{skyworkmath,
     title={SkyMath: Technical Report},
     journal={arXiv preprint arXiv: 2310.16713},
     url={https://arxiv.org/abs/2310.16713},
     ...
   }
   

Suggested fix — line 41:

[Skymath](https://arxiv.org/abs/2310.16713)