refactor: move analytics data deletion out of MetaMetrics (4/4 wallet-integrations) (MetaMask#26026)

## **Description**

Part 4/4 of MetaMask#25767 — **Code owner: wallet-integrations**

> **Independent** — can merge in any order.

Removes `updateDataRecordingFlag` from the MetaMetrics mock in
`ethereum-chain-utils.test.ts`. The production code
(`ethereum-chain-utils.js`) only calls
`MetaMetrics.getInstance().trackEvent()` — it never references
`updateDataRecordingFlag`, making this mock property dead code.

**What changed:**
- **`ethereum-chain-utils.test.ts`** — removed `updateDataRecordingFlag:
jest.fn()` from the `MetaMetrics.getInstance()` mock (1 line deleted).

## **Changelog**

CHANGELOG entry: null

## **Related issues**

This one is fixing the issue (PR 4 on 4):
Fixes: MetaMask#25767
Fixes: https://consensyssoftware.atlassian.net/browse/MCWP-297

## **Manual testing steps**

N/A — test-only change.

## **Screenshots/Recordings**

N/A — test-only change.

### **Before**

N/A

### **After**

N/A

## **Pre-merge author checklist**

- [x] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask Mobile
Coding
Standards](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [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](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.

## **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.


<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Low Risk**
> Test-only cleanup that removes dead mocking with no runtime behavior
changes.
> 
> **Overview**
> Cleans up the `switchToNetwork` analytics test by removing the unused
`updateDataRecordingFlag` stub from the `MetaMetrics.getInstance()` mock
in `ethereum-chain-utils.test.ts`.
> 
> No production logic changes; the test now only mocks `trackEvent`,
matching actual usage in `ethereum-chain-utils.js`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
c38c8c6. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: NicolasMassart

app/core/RPCMethods/lib/ethereum-chain-utils.test.ts

@@ -30,7 +30,6 @@ describe('switchToNetwork', () => {
     const mockTrackEvent = jest.fn();
     (MetaMetrics.getInstance as jest.Mock).mockReturnValue({
       trackEvent: mockTrackEvent,
-      updateDataRecordingFlag: jest.fn(),
     });
 
     const mockAddProperties = jest.fn().mockReturnThis();