fix: connect request completed source validation

[elefantel]

Description

The Connect Request Completed analytics event had a wrong source walletconnect when a dapp was connecting to the wallet from the in-app browser. This PR fixes source the validation.

Related issues

Fixes: SDK-81

Manual testing steps

1. Connect from a dapp within the in-app browser
2. Observe Request Completed` analytics event being logged

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]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

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

See analysis details on SonarCloud

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 4 lines in your changes missing coverage. Please review.

Project coverage is 54.21%. Comparing base (5b1d54a) to head (61e9a05).
Report is 16 commits behind head on main.

Files with missing lines	Patch %	Lines
...components/Views/AccountConnect/AccountConnect.tsx	0.00%	1 Missing and 3 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #11701      +/-   ##
==========================================
+ Coverage   54.07%   54.21%   +0.14%     
==========================================
  Files        1689     1709      +20     
  Lines       38546    38707     +161     
  Branches     4707     4736      +29     
==========================================
+ Hits        20844    20986     +142     
- Misses      16264    16272       +8     
- Partials     1438     1449      +11     

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