chore(sdk): Remove a useless import.

Author: Hywan

crates/matrix-sdk/src/event_cache/room/events.rs

@@ -19,7 +19,7 @@ pub use matrix_sdk_base::event_cache::{Event, Gap};
 use matrix_sdk_base::{
     apply_redaction,
     event_cache::store::DEFAULT_CHUNK_CAPACITY,
-    linked_chunk::{ChunkContent, LinkedChunkBuilder, LinkedChunkBuilderError, RawChunk},
+    linked_chunk::{LinkedChunkBuilder, LinkedChunkBuilderError, RawChunk},
 };
 use matrix_sdk_common::linked_chunk::{
     AsVector, Chunk, ChunkIdentifier, EmptyChunk, Error, Iter, IterBackward, LinkedChunk,