Enable gzip compression for Sync PATCH payloads

[ayoy]

Please review the release process for BrowserServicesKit here.

Required:

Task/Issue URL: https://app.asana.com/0/0/1206919211758354/f iOS PR: https://github.com/duckduckgo/iOS/pull/2805 macOS PR: https://github.com/duckduckgo/macos-browser/pull/2723 What kind of version bump will this require?: Patch

Description: This change adds gzip compression to all Sync data PATCH requests.

Steps to test this PR:

1. Run both iOS and macOS apps from branches in linked PRs.
2. Connect devices with Sync and smoke test syncing data.

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Internal references:

Software Engineering Expectations Technical Design Template