fix: Add inline padding to Select

[evadecker]

Description

• Closes Select options are not centrally aligned #1552
• Supersedes fix: Better alignment of selected option within select box. #1939 (thanks @rgilsimoes!)
• Adds additional inline padding to the Select component with an equivalent negative inline margin to increase the hit area and give visual space between the outline and the contents of the component
• Does not affect existing alignment of text

Comparison:
https://github.com/withastro/starlight/assets/4117920/ed8851b1-afab-4d9c-8903-0c8c406fe26e

[changeset-bot]

🦋 Changeset detected

Latest commit: 4f25edc

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@astrojs/starlight	Patch

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Name	Status	Preview	Updated (UTC)
starlight	✅ Ready (Inspect)	Visit Preview	Jun 28, 2024 3:53pm

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[delucis]

Thanks again @evadecker — looks great!