chore(bench_util): fix syntax error in README.md

[zhanghengxin]

fix:Updating grammar errors in readme.md

fix #21491

[CLAassistant]

All committers have signed the CLA.

[dsherret]

@zhanghengxin Thanks! Once the CLA is signed then we can merge this.

[zhanghengxin]

@dsherret

The signing has been completed as requested.

[zhanghengxin]

@dsherret
What are the other things I need to do?

[dsherret]

@zhanghengxin I think just run ./tools/format.js and it should be good to go. That code block has started being formatted by the formatter now that it doesn't contain a syntax error.

[zhanghengxin]

@zhanghengxin I think just run ./tools/format.js and it should be good to go. That code block has started being formatted by the formatter now that it doesn't contain a syntax error.我认为只要跑一跑 ./tools/format.js ，它应该很好。该代码块已开始由格式化程序格式化，因为它不包含语法错误。

Because it is code in Markdown, nobody corrected it for two years.

[dsherret]

The CI for this PR is failing because the code is not formatted. Running ./tools/format.js then committing the changes will fix it and make the CI pass.

[zhanghengxin]

sorry , I misunderstood the meaning.I got to do!

[zhanghengxin]

Nothing changed after the formatting was performed

[kt3k]

LGTM