fix: Vertically center Banner text content when action or close button is present

[engfragui]

Description

Vertically centers <Banner>'s text content when action or close button is present.
Note that before this fix the text content was slightly closer to the top of the <Banner> and not actually centered.

Reference

• Raised by @rfgamaral in this comment
• Figma Web Component Library

Demo

Before	After
(Storybook)	(Storybook)

[doistbot]

This PR updates the Banner component to vertically center its text content when an action or close button is present, helping to create a more balanced layout. However, an issue was noted where applying align-items: center to the .content class inadvertently centers the text horizontally in the mobile view, alongside a minor redundancy in the desktop layout.

_{Share Feedback • Review Logs}

[doistbot]

This PR improves the visual balance of the Banner component by vertically centering its text content when an action or close button is present. While this nicely aligns the component with the design specifications, there is a layout regression in narrow containers (under 235px) where the updated structure causes the type icon and close button to inadvertently render on separate rows.

_{Share Feedback • Review Logs}