refactor: replace refresh & access token with auth token only

changes authentication to no longer use a refresh token & access token
for accessing protected endpoints. Instead only an auth token is used.

Before the login flow was:

Login -> get refresh (stored as HttpOnly cookie) + access token (stored in memory) ->
  protected endpoint request (attach access token as Authorization header) -> access token expires in
  15 minutes, so use refresh token to obtain new one when that happens

now it looks like this:

Login -> get auth token (stored as HttpOnly cookie) -> make protected endpont
request (token sent)

the reasoning for using the refresh + access token was to reduce DB
calls, but in the end I don't think its worth the hassle.

frontend/src/Projects/Project/Board/index.tsx

@@ -543,7 +543,7 @@ const ProjectBoard: React.FC<ProjectBoardProps> = ({ projectID, onCardLabelClick
                     onChangeTaskMetaFilter={filter => {
                       setTaskMetaFilters(filter);
                     }}
-                    userID={user?.id}
+                    userID={user ?? ''}
                     labels={labelsRef}
                     members={membersRef}
                   />,