docs(spindle-ui): ButtonのDesign DocにContained/Outlined並び順ガイドラインを追加

[MasatoHonda]

縦並び・横並び時のContainedボタンとOutlinedボタンの配置ルールを
スクリーンショットとDO/DO NOTに追記した。

[changeset-bot]

⚠️ No Changeset found

Latest commit: 193be00

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[github-actions]

Visit the preview URL for this PR (updated for commit 193be00):

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[reg-suit]

reg-suit detected visual differences.

Check this report, and review them.

🔴 Changed	⚪ New	🔵 Passing
5	1	253

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[herablog]

@MasatoHonda lint commit message(s) / lint commit message(s) (pull_request)だけ修正お願いします！

[MasatoHonda]

@herablog 修正しましたー
regで差分が出てるんですが、今回の変更箇所と関係ないところっぽいんですが、これはどうしましょう

[herablog]

VRTは確認して許容できるものなのでこのままで大丈夫です！残り以下対応お願いします。

[herablog]

記述と描画が違いそうっす

[MasatoHonda]

あ、これはStorybook側から考え直さないといけなかった可能性がありますね…？

[herablog]

Storybookの例が違ってたら直しちゃいたいっすね！

[herablog]