Cleaned up codeblock code + fixed up issue with bottom border

[lamATnginx]

Proposed changes

Closes https://github.com/nginxinc/docs-platform/issues/409

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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)

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[lamATnginx]

Seems to be an issue with playwright when pulling the artifact. Running again.

[nginx-jack]

I may need to tweak this for the overall spacing/gutter stuff, but this LGTM for now 👍