Fix navigator undefined on React Native

[radko93]

Small PR as everything is in the issue - fixes #3137

Checklist:

• If this PR is a new feature, please reference an issue where a consensus about the design was reached (not necessary for small changes)
• Make sure all of the significant new logic is covered by tests
• If this was a change that affects the external API used in GitHunt-React, update GitHunt-React and post a link to the PR in the discussion.

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	Warnings
⚠️	There are library changes, but not tests. That's OK as long as you're refactoring existing code

	Messages
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[peggyrayzis]

Thanks for making this fix! 🎉 Before I merge, can you please add an entry to the Changelog with a link to the PR?

[radko93]

@peggyrayzis done, thanks!

[gastonmorixe]

This is not solved. I still receive error in RN.

It should be

if (window && 
window.navigator && 
window.navigator.userAgent && 
window.navigator.userAgent.indexOf('Chrome') > -1)```