Fix some string mappings for link new device errors

[hughns]

Content

Some of the link new device error screens are currently using strings for the login flow (not the link new device flow).

This PR updates those screens to use the (previously unused) link_new_device_* strings.

Alternatively, the unused strings should be removed.

Motivation and context

Screenshots / GIFs

Tests

• Step 1
• Step 2
• Step ...

Tested devices

• Physical
• Emulator
• OS version(s):

Checklist

• This PR was made with the help of AI:
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  • No.
• Changes have been tested on an Android device or Android emulator with API 24
• UI change has been tested on both light and dark themes
• Accessibility has been taken into account. See https://github.com/element-hq/element-x-android/blob/develop/CONTRIBUTING.md#accessibility
• Pull request is based on the develop branch
• Pull request title will be used in the release note, it clearly defines what will change for the user
• Pull request includes screenshots or videos if containing UI changes
• You've made a self review of your PR

[github-actions]

Thank you for your contribution! Here are a few things to check in the PR to ensure it's reviewed as quickly as possible:

• If your pull request adds a feature or modifies the UI, this should have an equivalent pull request in the Element X iOS repo unless it only affects an Android-only behaviour or is behind a disabled feature flag, since we need parity in both clients to consider a feature done. It will also need to be approved by our product and design teams before being merged, so it's usually a good idea to discuss the changes in a Github issue first and then start working on them once the approach has been validated.
• Your branch should be based on origin/develop, at least when it was created.
• The title of the PR will be used for release notes, so it needs to describe the change visible to the user.
• The test pass locally running ./gradlew test.
• The code quality check suite pass locally running ./gradlew runQualityChecks.
• If you modified anything related to the UI, including previews, you'll have to run the Record screenshots GH action in your forked repo: that will generate compatible new screenshots. However, given Github Actions limitations, it will prevent the CI from running temporarily, until you upload a new commit after that one. To do so, just pull the latest changes and push an empty commit.

[jmartinesp]

I think you need to record new screenshots:

If you modified anything related to the UI, including previews, you'll have to run the Record screenshots GH action in your forked repo: that will generate compatible new screenshots. However, given Github Actions limitations, it will prevent the CI from running temporarily, until you upload a new commit after that one. To do so, just pull the latest changes and push an empty commit.

That said, recording screenshots may be failing for forks at the moment. I'm trying to figure out if it's a permission issue in a fork of mine.

---

That should be fixed once #6679 is merged.

---

Ok, the fix is merged in develop and this branch was updated. @hughns can you record new screenshots?

[bmarty]

That sounds good, thanks!
Do not bother about the unused strings, I can handle that later.
Waiting for the screenshots to be updated before approving the changes.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.21%. Comparing base (90ed385) to head (3aa92a5).
⚠️ Report is 4 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #6675      +/-   ##
===========================================
- Coverage    81.22%   81.21%   -0.01%     
===========================================
  Files         2628     2628              
  Lines        73255    73255              
  Branches      9494     9494              
===========================================
- Hits         59499    59494       -5     
- Misses       10270    10277       +7     
+ Partials      3486     3484       -2     

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[bmarty]

Note: this screen should never be displayed, when Link new device with QR code is not supported, this is handled by LinkNewDeviceRootView and the screen is:

[jmartinesp]

@hughns I think we need to merge the develop branch or rebase it, then record new screenshots.