[#5846] Remove custom user agent to fix captcha failure loop

[g1a55er]

Contributor checklist

• My commits are rebased on the latest main branch
• My commits are in nice logical chunks
• My contribution is fully baked and is ready to be merged as is
• I have tested my contribution on these devices:

• iPhone 15 Pro, iOS 17.6.1

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Description

I was also hit by the bug filed as #5846, where I get stuck in an infinite "Something went wrong" captcha failure loop on registration with notifications unavailable.

After some debugging, comparing iOS and Android, it turns out this traces back to hCaptcha not liking the custom user agent of the WebView used for the CAPTCHA view

Once I removed the custom user agent so that the WebView goes back to the default user agent, I am able to successfully get out of the failure loop.

[luoye1101]

I deleted the custom user agent in your way, but the problem still exists

[OscillateWildly]

I'd like to raise the profile of this proposed fix, as if this does indeed resolve the described issue, it will resolve an inability to change phone numbers currently being experienced/reported by myself and others.