Update README.md

[yqtianust]

the link of quick start is invalid.

Motivation

fix the issue of invalid link in readme.

Modifications

Update a link in README.md

Checklist

• Format your code according to the Code Formatting with Pre-Commit.
• Add unit tests as outlined in the Running Unit Tests.
• Update documentation / docstrings / example tutorials as needed, according to Writing Documentation.
• Provide throughput / latency benchmark results and accuracy evaluation results as needed, according to Benchmark and Profiling and Accuracy Results.
• For reviewers: If you haven't made any contributions to this PR and are only assisting with merging the main branch, please remove yourself as a co-author when merging the PR.
• Please feel free to join our Slack channel at https://slack.sglang.ai to discuss your PR.

[Fridge003]

Repeated PR in #3588

[zhaochenyang20]

#3588

@yqtianust Thanks. We give you the credit.

[yqtianust]

Thanks a lot!