Fix add custom token

[jpcloureiro]

Description

Fix payload when adding a custom token (wallet_watchAsset rpc call). Also use the token logo if provided.

wallet_watchAsset rpc method spec

Checklist

• There is a related GitHub issue
• Tests are included if applicable
• Any added code is fully documented

Issue

Resolves #3722

[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.

[jpcloureiro]

I have read the CLA Document and I hereby sign the CLA

[gantunesr]

Good work @jpcloureiro! Left some comments

[gantunesr]

LGTM

[chrisleewilcox]

Getting the following error when running yarn setup...

**ERROR** Failed to apply patch for package @metamask/design-tokens at path
  
    node_modules/@metamask/design-tokens

  This error was caused because @metamask/design-tokens has changed since you
  made the patch file for it. This introduced conflicts with your patch,
  just like a merge conflict in Git when separate incompatible changes are
  made to the same piece of code.

  Maybe this means your patch file is no longer necessary, in which case
  hooray! Just delete it!

  Otherwise, you need to generate a new patch file.

  To generate a new one, just repeat the steps you made to generate the first
  one.

  i.e. manually make the appropriate file changes, then run 

    patch-package @metamask/design-tokens

  Info:
    Patch file: patches/@metamask+design-tokens+1.4.2.patch
    Patch was made for version: 1.4.2
    Installed version: 1.5.1

---
patch-package finished with 1 warning(s), 1 error(s).
4. Create xcconfig files...
5. Init git submodules

[wachunei]

@chrisleewilcox this was fixed here b9d3f4b, updating this branch with main will fix it.

[chrisleewilcox]

Here is a recording of the test. Data is shown as expected and token icon is shown.

https://recordit.co/pjMnCIaTr4

LGTM