test(sdk): Test the RoomEvents' methods.

This patch adds unit tests for the `RoomEvents`' methods.

Author: Hywan

crates/matrix-sdk/src/event_cache/linked_chunk/mod.rs

@@ -852,6 +852,13 @@ impl ChunkIdentifierGenerator {
 #[repr(transparent)]
 pub struct ChunkIdentifier(u64);
 
+#[cfg(test)]
+impl PartialEq<u64> for ChunkIdentifier {
+    fn eq(&self, other: &u64) -> bool {
+        self.0 == *other
+    }
+}
+
 /// The position of something inside a [`Chunk`].
 ///
 /// It's a pair of a chunk position and an item index.