fix: use correct string type in network diagnostics handler

[a7medev]

Description of the change

The type of the data parameter in NetworkDiagnosticsHandler was set to String which is the object wrapper around the string type, this causes TypeScript errors when trying to assign data to a variable of type string. So we changed it to string.

Type of change

• [x] Bug fix (non-breaking change that fixes an issue)
• [ ] New feature (non-breaking change that adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

Related issues

Jira ID: INSD-11050

Checklists

Development

• [ ] Lint rules pass locally
• [ ] The code changed/added as part of this pull request has been covered with tests

Code review

• [ ] This pull request has a descriptive title and information useful to a reviewer
• [ ] Issue from task tracker has a link to this pull request

[InstabugCI]

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Coverage Report

Label	Coverage	Status
JavaScript	96.3%	✅
Android	46.9%	✅
iOS	42.2%	✅

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