fix: token details view undefined value

[gambinish]

Description

Fixes token details view when tokenExchangeRates have not yet resolved, or are simply undefined.

Related issues

Fixes: #11539

Manual testing steps

1. Go to TokenDetails
2. Hardcode tokenExchangeRates to undefined
3. App should not crash. Token details will be empty. Error was when pressing native gas token, but also check others.

Screenshots/Recordings

Bug:

Fix:

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: 6005a74
Build link: https://app.bitrise.io/app/be69d4368ee7e86d/pipelines/09b07c29-19da-4a84-bea9-dc57f0b24e7d

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

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
66.7% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud