Ensure navigation bar in project form pages are sticky

[juancwu]

Description

This PR makes the navigation bar for all project form pages sticky.

Also made the "back to dashboard" link's clickable area bigger and hover effect.

Linked Issues

• Closes [FE Feat] Ensure the form section navigation tabs are sticky #424

Checklist

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• Has an assignee or group of assignees.
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• Has an assigned milestone.

Additionally, make sure that:

• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• I have added tests that prove my fix is effective or that my feature works.
• New and existing unit tests pass locally with my changes.
• Any dependent changes have been merged and published in downstream modules.

[aidantrabs]

lgtm