components

## **Description**
Updated theme tokens in QR-related tokens from this.context.theme to
this.context. This correctly exposes the colors and brandColors needed.
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Write a short description of the changes included in this pull request,
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## **Related issues**

Fixes:
https://app.zenhub.com/workspaces/mobile-release-testing-6249e5242464b70013315a98/issues/gh/metamask/mobile-planning/1529

## **Manual testing steps**

1. Go to Wallet
2. Click on Actions
3. Click on Receive

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**

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### **After**

https://github.com/MetaMask/metamask-mobile/assets/14355083/215790d9-a758-45bc-82cc-711a767b92f2

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## **Pre-merge author checklist**

- [x] I’ve followed [MetaMask Coding
Standards](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've clearly explained what problem this PR is solving and how it
is solved.
- [x] I've linked related issues
- [x] I've included manual testing steps
- [x] I've included screenshots/recordings if applicable
- [ ] I’ve included tests if applicable
- [x] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [x] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.
- [x] I’ve properly set the pull request status:
  - [ ] In case it's not yet "ready for review", I've set it to "draft".
- [ ] In case it's "ready for review", I've changed it from "draft" to
"non-draft".

## **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.