[Message actions] New UI for message composer and editing (#526)

* Add UI for edit composer mode

* Remove leftover code from the RTE implementation

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Co-authored-by: ElementBot <benoitm+elementbot@element.io>

.maestro/tests/roomList/searchRoomList.yaml

@@ -5,8 +5,6 @@ appId: ${APP_ID}
 - inputText: ${ROOM_NAME.substring(0, 3)}
 - takeScreenshot: build/maestro/400-SearchRoom
 - tapOn: ${ROOM_NAME}
-# Close keyboard
-- hideKeyboard
 # Back from timeline
 - back
 # Close keyboard

.maestro/tests/roomList/timeline/timeline.yaml

@@ -4,10 +4,8 @@ appId: ${APP_ID}
 # TODO Create a room on a new account
 - tapOn: ${ROOM_NAME}
 - takeScreenshot: build/maestro/500-Timeline
-- tapOn: "Message…"
+- tapOn: "Message"
 - inputText: "Hello world!"
-- tapOn: "Toggle full screen mode"
-- tapOn: "Toggle full screen mode"
 - tapOn: "Send"
 - hideKeyboard
 - back