Update to serialize unsaved instances using local ID's

[habdelra]

This PR updates our serialization of cards to serialize unsaved cards using the "lid" property which holds the local ID of the card (this is part of the JSON-API spect). This will facilitate our ability to optimistically create cards and potentially send the server an unsaved link to save.

[github-actions]

Host Test Results

  1 files  ±0    1 suites  ±0   31m 18s ⏱️ +3s
947 tests +2  941 ✅ +2  6 💤 ±0  0 ❌ ±0 
954 runs  +2  948 ✅ +2  6 💤 ±0  0 ❌ ±0 

Results for commit c67e790. ± Comparison against base commit 46ab4b8.

This pull request removes 1 and adds 3 tests. Note that renamed tests count towards both.

Chrome ‑ Integration | serialization: throws when serializing a linksTo relationship to an unsaved card

Chrome ‑ Integration | serialization > linksToMany: can serialize a linksToMany relationship with unsaved links
Chrome ‑ Integration | serialization: can serialize a linksTo relationship with an unsaved card
Chrome ‑ Integration | serialization: can serialize an unsaved linksTo relationship that points to itself

♻️ This comment has been updated with latest results.