refactor: rename the feature flag since it had a typo

[EtherWizard33]

Description

This PR just renames the feature flag since it had a typo, making it difficult to find for someone looking for multichain since mu-l-ti had a typo.

Related issues

Fixes:

Manual testing steps

1. To test without the mutlichain mocked screens, in js.env toggle the feature flag off (the default is also off) by setting export MM_MULTICHAIN_V1_ENABLED=""
2. Then connect to a dapp via the in-app browser and see the current screens currently used in prod
3. To enable mulitichain mocked screens, set the export MM_MULTICHAIN_V1_ENABLED="1" and connect to a dapp to see new mocked multichain screens

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.

[github-actions]

CLA Signature Action: All authors have signed the CLA. You may need to manually re-run the blocking PR check if it doesn't pass in a few minutes.

[github-actions]

Bitrise

✅✅✅ pr_smoke_e2e_pipeline passed on Bitrise! ✅✅✅

Commit hash: ff083ea
Build link: https://app.bitrise.io/app/be69d4368ee7e86d/pipelines/52d48109-90b7-405c-a309-8f965f209c41

Note

• You can kick off another pr_smoke_e2e_pipeline on Bitrise by removing and re-applying the Run Smoke E2E label on the pull request

[NicolasMassart]

Looks good to me.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
69.8% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud