feat(snaps): Add integration for snap_trackEvent RPC method (#32554)

## **Description**
This PR adds integration for new Snap RPC method called
`snap_trackEvent`.

The implementation is done in Snaps repositories in the following PR:
MetaMask/snaps#3375

Method specification: https://metamask.github.io/SIPs/SIPS/sip-32

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## **Related issues**
Fixes: MetaMask/snaps#3274

## **Manual testing steps**
1. Within some of the preinstalled Snaps use `snap_trackEvent` RPC
method and send some tracking data in format specified in
[SIP-32](https://metamask.github.io/SIPs/SIPS/sip-32).
2. Find a way and verify that the event is sent (intercept MetaMetrics
track event method or check with other e2e metrics testing utilities)

Example Snap code used for testing the method:
```typescript
await snap.request({
  method: 'snap_trackEvent',
  params: {
    event: {
      event: 'SnapExportUsed',
      properties: {
        export: 'onRpcRequest',
        origin: 'https://metamask.io',
        snap_category: null,
        snap_id: 'npm:@metamask/example-snap',
        success: true,
      },
      sensitiveProperties: {
        transaction_hash: 'transaction-hash',
      },
    },
  },
});
```

## **Screenshots/Recordings**
### **Before**
No UI changes (n/a).

### **After**
No UI changes (n/a).

## **Pre-merge author checklist**
- [ ] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [ ] 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](https://jsdoc.app/) format
if applicable
- [ ] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-extension/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.

Author: david0xd

app/scripts/controllers/permissions/specifications.js

@@ -193,6 +193,7 @@ export const unrestrictedMethods = Object.freeze([
   'snap_cancelBackgroundEvent',
   'snap_getBackgroundEvents',
   'snap_experimentalProviderRequest',
+  'snap_trackEvent',
   ///: BEGIN:ONLY_INCLUDE_IF(build-mmi)
   'metamaskinstitutional_authenticate',
   'metamaskinstitutional_reauthenticate',

app/scripts/metamask-controller.js

@@ -7132,6 +7132,9 @@ export default class MetamaskController extends EventEmitter {
           this.controllerMessenger,
           'SnapController:get',
         ),
+        trackEvent: this.metaMetricsController.trackEvent.bind(
+          this.metaMetricsController,
+        ),
         getAllSnaps: this.controllerMessenger.call.bind(
           this.controllerMessenger,
           'SnapController:getAll',