Fix robber discard for robots

Signed-off-by: James Ketrenos <james_eikona@ketrenos.com>

server/ai/app.js

@@ -735,7 +735,7 @@ const message = async (data) => {
       if (!isMatch(waitingFor, received)) {
         console.log(`${name} - still waiting - waitingFor: `,
           waitingFor);
-        if (game.robberInAction) {
+        if (game.turn && game.turn.robberInAction) {
           console.log(`${name} - robber in action! Must check discards...`);
         } else {
           return;