Fix heading anchor link icon alignment

[lamATnginx]

Proposed changes

Before:

After:

Edge case (mulit-line text):

Checklist

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• I have read the CONTRIBUTING document
• If applicable, I have added tests that prove my fix is effective or that my feature works
• If applicable, I have checked that any relevant tests pass after adding my changes
• I have updated any relevant documentation (README.md and CHANGELOG.md)

[github-actions]

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