Update GeneralPage: Back-up UI

[Jay-o-Way]

Summary of the Pull Request

Note superseeded by #21317 Niels: If you see anything specific you like, you're free to use it.

UI tweaks:

• add space between buttons (as in 21844)
• changed 2 Grids to StackPanels
• vertical alignment of the folder path
• order of details (personal choice)

Open questions:

• I think Setting.Description > TextBlock > Run General_SettingsBackupAndRestoreDescription (line 236-240) can/should be simplified?
• Same question for 8× TextBlock > Run (lines 280~312)

PR Checklist

• [x] Closes: #21844
• [ ] Communication: I've discussed this with core contributors already. If work hasn't been agreed, this work might be rejected
• [ ] Tests: Added/updated and all pass
• [x] Localization: All end user facing strings can be localized
• [ ] Dev docs: Added/updated
• [ ] New binaries: Added on the required places
  • [ ] JSON for signing for new binaries
  • [ ] WXS for installer for new binaries and localization folder
  • [ ] YML for CI pipeline for new test projects
  • [ ] YML for signed pipeline
• [ ] Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

Validation Steps Performed

Visual Studio