Update settings panel design

[SajidAlamQB]

Description

Related to: https://github.com/kedro-org/kedro-viz/issues/1752

Following the PR, https://github.com/kedro-org/kedro-viz/pull/1858, the implementation has been completed but there are still a few design changes @stephkaiser has noticed that will be addressed in this PR.

Development notes

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Checklist

• [x] Read the contributing guidelines
• [x] Opened this PR as a 'Draft Pull Request' if it is work-in-progress
• [x] Updated the documentation to reflect the code changes
• [x] Added new entries to the RELEASE.md file
• [ ] Added tests to cover my changes