Add Storybook, Confluence and Jira social icons

[Sidnioulz]

Description

Adds three icons: Storybook, Confluence and Jira

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🦋 Changeset detected

Latest commit: f038a76

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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[delucis]

Thanks for the PR @Sidnioulz! All looks great to me — just suggested one small optimisation.

[Sidnioulz]

Thanks for the review @delucis! I did send the icons through SVGOMG but I'm quite conservative with precision rounding so I didn't optimise them as much as you did :)