test(sdk): Add test for maybe_apply_new_redaction

[Hywan]

Follow up of #4740. I forgot to add a test!

This patch adds a test for maybe_apply_new_redaction when the redacted event is not loaded in-memory, i.e. when it lives in the store only.

---

• Address [meta] EventCache storage #3280

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.28%. Comparing base (1d7c60c) to head (30a1eea).
Report is 29 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4760   +/-   ##
=======================================
  Coverage   86.28%   86.28%           
=======================================
  Files         290      290           
  Lines       34281    34281           
=======================================
+ Hits        29578    29581    +3     
+ Misses       4703     4700    -3     

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[poljar]

Thanks for adding the forgotten test. I left a small suggestion but feel free to ignore.

[poljar]

Suggested change

	AnySyncTimelineEvent::MessageLike(AnySyncMessageLikeEvent::RoomMessage(event)) => {
	// The event has been redacted!
	assert!(event.as_original().is_none());
	AnySyncTimelineEvent::MessageLike(event) => {
	// The event has been redacted!
	assert!(event.is_redacted());

Not quite the same, but if we only care about the fact that the event is redacted might be nicer to read.

[Hywan]

Cool, didn't know about this one! Fixed up and rebased.