refactor: replace deprecated mixins with text component in transaction-confirmed

[devin-ai-integration[bot]]

Description

This pull request replaces deprecated mixins with the Text component in the transaction-confirmed.component.js file. The padding values in the Text components have been updated to 4.

Devin Run Link: https://staging.itsdev.in/devin/0bf228de1dc64981adb90e7ac712d1e7

Related issues

Partially Fixes: https://github.com/MetaMask/metamask-extension/issues/20496

Manual testing steps

1. Go to the latest build of storybook in this PR
2. Manually check if TransactionConfirmed is getting rendered correctly

Screenshots/Recordings

Before

After

Pre-merge author checklist

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

Pre-merge reviewer checklist

• [x] I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• [x] 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.