Fix edge case behaviour of the space join spinner for guests

src/components/structures/SpaceRoomView.tsx

@@ -275,8 +275,11 @@ const SpacePreview = ({ space, onJoinButtonClicked, onRejectButtonClicked }: ISp
             <AccessibleButton
                 kind="primary"
                 onClick={() => {
-                    setBusy(true);
                     onJoinButtonClicked();
+                    if (!cli.isGuest()) {
+                        // user will be shown a modal that won't fire a room join error
+                        setBusy(true);
+                    }
                 }}
                 disabled={!spacesEnabled || cannotJoin}
             >