[Icon] Update Tablet icon design

[trtri2]

WHY are these changes introduced?

part of https://github.com/Shopify/retail-hq-store-management/issues/558

exported the icon SVG from this figma

• Update the tablet icon to the new design (it was previously too similar to the mobile icon to distinguish the two)

How to 🎩

🖥 Local development instructions
🗒 General tophatting guidelines
📄 Changelog guidelines

🎩 checklist

• Tested a snapshot
• Tested on mobile
• Tested on multiple browsers
• Tested for accessibility
• Updated the component's README.md with documentation changes
• Tophatted documentation changes in the style guide

[alex-page]

@trtri2 what is the timeline and need for this adjustment? Can this wait? We are rebuilding the icon library right now.

[trtri2]

@trtri2 what is the timeline and need for this adjustment? Can this wait? We are rebuilding the icon library right now.

Hey @alex-page.

We received some UX feedback on one of our POS app UI editors, where you can change device preview to mobile or tablet.
Currently, the two icons are nearly indistinguishable. Ideally we'd like to have this improvement in sooner rather than later, but it's non-critical so shouldn't be a blocker for it.

If we were to wait for this rebuild, do you have a timeline/estimate on that which I can communicate to my team and let them know?

[alex-page]

@trtri2 please review the 16x16 viewbox in this PR https://github.com/Shopify/admin-ui-foundations/pull/660

[trtri2]

Closing in favour for the new admin ui library