fix: adding max with to send page in expanded view

[georgewrmarshall]

Description

This pull request introduces a maximum width of 480px to the send screen in expanded view. This change is intended to enhance the user interface by preventing it from taking up 100% of the screen width on larger screens, thereby improving the visual presentation and user experience.

Related slack thread

https://warpcast.com/antimofm.eth/0x487c8c0e

Related issues

Fixes: N/A

Manual testing steps

1. Open the extension in expanded view
2. Select "Send" button from home page
3. See send screen is no longer 100% width of large screens

Screenshots/Recordings

Before

before720.mov

After

after720.mov

Pre-merge author checklist

• I've followed MetaMask Contributor Docs and MetaMask Extension Coding Standards.
• I've completed the PR template to the best of my ability
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format if applicable
• I’ve applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.

[github-actions]

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[georgewrmarshall]

This aligns with our container component and the max width set. The reason I didn't use the Container component is that it would require a fair amount of refactoring.

[georgewrmarshall]

Seems like this has been resolved