Introduced a new case to reduceMessageStore which was when the sendReactionMessageActionTypes success type gets dispatched. Like a lot of the other cases in reduceMessageStore when this case is true, it returns the new message store with the merged messages in them, so in this case the newly created reaction message
Depends on D5780
Linear Task: ENG-2246
Why bind mount a temp directory instead of using a data volume? It's just gonna create issues with permissions. Also ${TMPDIR} is not used to refer to a path in both the host and the container which is a bad idea.