Remove obsolete iOS sync logic

[lougeniaC64]

This is the last piece of the iOS sync manager integration work. At a high level, it removes the sync functionality we exposed for iOS prior to the sync manager integration. It includes:

• Removing the reset, wipe, and sync functions from the swift layer of the logins component
• Removing the sync function from the logins UDL and store files
• Removing the syncBookmarks, syncHistory, resetHistorySyncMetadata, resetBookmarksSyncMetadata, and wipeLocalHistory functions from the swift layer of the places component
• Removing the reset and sync functions from the swift layer of the tabs component
• Removing the reset and sync functions from the tabs UDL and full sync module
• Removing the full-sync tabs feature (which required updating a number of cargo files)
• Refactoring the sync logic in the sync-pass and tabs-sync examples

NOTE: I've purposely excluded any changes that would necessitate updating A-C so that the scope of the sync manager integration effort isn't increased.

Pull Request checklist

• Breaking changes: This PR follows our breaking change policy
  • This PR follows the breaking change policy:
    • This PR has no breaking API changes, or
    • There are corresponding PRs for our consumer applications that resolve the breaking changes and have been approved
• Quality: This PR builds and tests run cleanly
  • Note:
    • For changes that need extra cross-platform testing, consider adding [ci full] to the PR title.
    • If this pull request includes a breaking change, consider cutting a new release after merging.
• Tests: This PR includes thorough tests or an explanation of why it does not
• Changelog: This PR includes a changelog entry in CHANGELOG.md or an explanation of why it does not need one
  • Any breaking changes to Swift or Kotlin binding APIs are noted explicitly
• Dependencies: This PR follows our dependency management guidelines
  • Any new dependencies are accompanied by a summary of the due dilligence applied in selecting them.

Branch builds: add [firefox-android: branch-name] to the PR title.

[tarikeshaq]

This looks great!! 🚀 🚀 Thank you for seeing this through!