refactor(sdk,ui): Remove `RoomEventCacheUpdate::AddTimelineItems` #13441

Job	Run time
Generate Crypto FFI Apple XCFramework	4m 17s
Run Complement Crypto tests / tests	7m 51s
xtask / xtask-🐧	5s
xtask / xtask-🍏	8s
matrix-rust-components-kotlin	4m 35s
matrix-rust-components-swift	8m 4s
Test UniFFI bindings generation	2m 3s
	27m 3s

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