Fix unintended underlines between badges in README

[kazutoiris]

What is the purpose of the change

This PR removes unintended underlines between badges in the README to enhance visual consistency and polish the layout.

Related issues/PRs

None.

Brief change log

• Resolve visual issues caused by whitespace text nodes triggering default link underlines
• Reformat the file

Checklist

• I have read the Contributing Guidelines on pull requests.
• I have explained the need for this PR and the problem it solves
• I have explained the changes or the new features added to this PR
• I have added tests corresponding to this change
• I have updated the documentation to reflect this change
• I have verified that this change is backward compatible (If not, please discuss on the Linkis mailing list first)
• If this is a code change: I have written unit tests to fully verify the new behavior.