fixes: #12857

Description

This PR corrects a linting issue and accidental typo in two files which could cause our banner to render full width instead of with the intended marginHorizontal.

We can see that both files where this typo exists has corresponding references to this style which will be affected (by not being applied). The codebase has been searched for all instances and these two were flagged. It's obvious by looking at the two changes that they need to be camelCase

Related issues

Fixes:

Manual testing steps

1. Trigger STX migration and use ApproveTransactionReview by using the testdapp in mobile to deploy a smart contract.
2. Ensure that the Smart TransactionMigrationBanner displays with proper margin and does not take up full width in this view. See screenshots where BEFORE is the existing state with the typo causing the banner to not display properly in the TransactionReview and the ApproveTransactionReview, views and the AFTER is with the fix to use camelCase as intended.

Screenshots/Recordings

Before

After

Pre-merge author checklist

• I’ve followed MetaMask Contributor Docs and MetaMask Mobile 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.