Add Maestro tests for create & join rooms (#472)

I created 2 additional test users to use them as MXID we lookup during room creation.

I.e. we will not login as those users, it's just 2 known MXIDs that we know exist so we can look them up.

- https://github.com/vector-im/element-x-android/issues/409

.maestro/tests/roomList/roomContextMenu.yaml

@@ -0,0 +1,14 @@
+appId: ${APP_ID}
+---
+# Purpose: Test the context menu of a room in the room list
+- longPressOn: ${ROOM_NAME}
+- takeScreenshot: build/maestro/310-RoomList-ContextMenu
+- tapOn:
+    text: "Settings"
+    index: 0
+- tapOn: "Back"
+- longPressOn: ${ROOM_NAME}
+- tapOn:
+    text: "Leave room"
+    index: 0
+- tapOn: "Cancel"