fix: refactor mechanism for sending analytics events

[frankvonhoven]

Description

Filter out nested objects like { anonymous: true, value: "ETH" } instead of a single value ETH that are showing up in analytics events since the migration from Mixpanel to Segment.

Related issues

Fixes: #9233

Manual testing steps

1. Go to Send Page
2. Send a transaction
3. Should see data in analytics dashboard for active_currency as single value and not an object

Screenshots/Recordings

Before

After

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[github-actions]

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[sethkfman]

LGTM

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
93.3% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud