Added margin-bottom for all sidebar

[pranjalisr]

Added margin-bottom for all sidebar link items. For bug issue #5813

Introduced consistent vertical spacing for Roadmap sidebar navigation by applying a flex column layout with a gap, using existing spacing tokens.
This ensures uniform spacing between all navigation links and prevents the active item from collapsing spacing.

Implementation Details

Scoped the change to .roadmap-sidebar nav
Used gap instead of margins to avoid margin-collapse issues
Reused existing design tokens for spacing consistency
No DOM or JavaScript changes

Impact

Improves readability and visual hierarchy of sidebar navigation
Fixes spacing inconsistency for the active item
Visual-only change with low risk of regression

[google-cla]

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[jrobbins]

I don't see the original problem that you described and I don't see any visual difference between this PR and the layout. However, using flex and gap does seem likely to be more consistent for the future. I'm willing to approve and merge this change, but first you need to sign the CLA (see the automated comment earlier on this PR).

[pranjalisr]

I don't see the original problem that you described and I don't see any visual difference between this PR and the layout. However, using flex and gap does seem likely to be more consistent for the future. I'm willing to approve and merge this change, but first you need to sign the CLA (see the automated comment earlier on this PR).

Thanks for the review!
I’ve now signed the CLA and completed all the required steps. Please let me know if there’s anything else needed from my side.
Appreciate your willingness to approve and merge the change — thanks!