fix format

[YesterdayxD]

Ⅰ. Describe what this PR did

fix markdown format and make it read easier

Ⅱ. Does this pull request fix one issue?

Ⅲ. Why don't you add test cases (unit test/integration test)? (你真的觉得不需要加测试吗？)

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[pouchrobot]

Thanks for your contribution. 🍻 @YesterdayxD
While we thought PR TITLE could be more specific, longer than 20 chars.
Please edit this PR title instead of opening a new one.
More details, please refer to https://github.com/dragonflyoss/Dragonfly/blob/master/CONTRIBUTING.md

[pouchrobot]

@YesterdayxD Thanks for your contribution. 🍻
Please sign off in each of your commits.

[pouchrobot]

We found this is your first time to contribute to Dragonfly, @YesterdayxD
👏 We really appreciate it.
Just remind that you have read the contribution guide: https://github.com/dragonflyoss/Dragonfly/blob/master/CONTRIBUTING.md
If you didn't, you should do that first. If done, welcome again and please enjoy hacking! 🍻

[codecov-commenter]

Codecov Report

Merging #1412 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1412   +/-   ##
=======================================
  Coverage   52.52%   52.52%           
=======================================
  Files         138      138           
  Lines        9185     9185           
=======================================
  Hits         4824     4824           
  Misses       3975     3975           
  Partials      386      386           

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[allencloud]

It will LGTM until you sign your commits. @YesterdayxD

[YesterdayxD]

It will LGTM until you sign your commits. @YesterdayxD

I got it.

[YesterdayxD]

rerun test

[allencloud]

LGTM