Reduce EdgeCanvas width to 120px and parameterize card and edge width

[kwasi]

/area metadata /area front-end /kind feature /assign @avdaredevil

Changes

• EdgeCanvas width is reduced by 80px total (requested by UX)

Before:

• https://screenshot.googleplex.com/WmcEciDEVF8
• https://screenshot.googleplex.com/3aZJr9ba1zM (200px edge canvas)

After:

• https://screenshot.googleplex.com/NMbCnqry2ea
• https://screenshot.googleplex.com/uHViiuPn7qE (120px edge canvas)

Implementation Changes

• <EdgeCanvas /> and <LineageCard /> width are controlled by constants in LineageCss.ts
• Column width padding is now based on the <EdgeCanvas /> width
• Column width is now equal to the card width

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This change is 

[avdaredevil]

/lgtm /approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: avdaredevil

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