Send full user agent header to server during OIDC authentication and when viewing Account and Device management screens

[hughns]

This is the equivalent of element-hq/element-x-ios#4106 but in Element Classic.

It allows the home server account management screens to see the full Element User-Agent even when running inside an ASWebAuthenticationSession.

Pull Request Checklist

• I read the contributing guide
• UI change has been tested on both light and dark themes, in portrait and landscape orientations and on iPhone and iPad simulators
• Accessibility has been taken into account.

• Pull request is based on the develop branch

• Pull request contains a changelog file in ./changelog.d
• You've made a self review of your PR
• Pull request includes screenshots or videos of UI changes
• Pull request includes a sign off

[codecov]

Codecov Report

❌ Patch coverage is 0% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 16.57%. Comparing base (acfac7c) to head (c08b257).
⚠️ Report is 5 commits behind head on develop.

Files with missing lines	Patch %	Lines
...uthentication/SSO/SSOAuthentificationSession.swift	0.00%	6 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #7997      +/-   ##
===========================================
+ Coverage    15.19%   16.57%   +1.38%     
===========================================
  Files         1815     1815              
  Lines       119414   119420       +6     
  Branches     47786    47787       +1     
===========================================
+ Hits         18143    19795    +1652     
+ Misses      100603    98955    -1648     
- Partials       668      670       +2     

Flag	Coverage Δ
uitests	59.68% <ø> (+10.06%)	⬆️
unittests	8.80% <0.00%> (-0.01%)	⬇️

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