Create tests

libraries/matrixui/src/main/kotlin/io/element/android/libraries/matrix/ui/components/MatrixUserProvider.kt

@@ -28,9 +28,14 @@ open class MatrixUserProvider : PreviewParameterProvider<MatrixUser> {
         )
 }
 
-fun aMatrixUser(id: String = "@id_of_alice:server.org", displayName: String = "Alice") = MatrixUser(
+fun aMatrixUser(
+    id: String = "@id_of_alice:server.org",
+    displayName: String = "Alice",
+    avatarUrl: String? = null,
+) = MatrixUser(
     userId = UserId(id),
     displayName = displayName,
+    avatarUrl = avatarUrl,
 )
 
 fun aMatrixUserList() = listOf(