Make BaseRoom.getDirectRoomMember change when roomInfo.isDm changes (#6989)

With `derivedStateOf` this wasn't working as expected for some reason, resulting in the dm member being null and displaying the wrong `RoomType` in the room details screen

libraries/matrixui/src/main/kotlin/io/element/android/libraries/matrix/ui/room/MatrixRoomMembers.kt

@@ -13,6 +13,7 @@ import androidx.compose.runtime.State
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.derivedStateOf
 import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import io.element.android.libraries.matrix.api.core.UserId
 import io.element.android.libraries.matrix.api.room.BaseRoom
@@ -42,10 +43,8 @@ fun getRoomMemberAsState(roomMembersState: RoomMembersState, userId: UserId): St
 @Composable
 fun BaseRoom.getDirectRoomMember(roomMembersState: RoomMembersState): State<RoomMember?> {
     val roomInfo by roomInfoFlow.collectAsState()
-    return remember {
-        derivedStateOf {
-            roomMembersState.getDirectRoomMember(roomInfo, sessionId)
-        }
+    return remember(roomInfo.isDm) {
+        mutableStateOf(roomMembersState.getDirectRoomMember(roomInfo, sessionId))
     }
 }