Only random discard hand at end phase

ygoenv/ygoenv/ygopro/ygopro.h

@@ -3836,6 +3836,8 @@ private:
       }
 
       if (discard_hand_) {
+        discard_hand_ = false;
+        if (current_phase_ == PHASE_END) {
           // random discard
           std::vector<int> comb(size);
           std::iota(comb.begin(), comb.end(), 0);
@@ -3845,9 +3847,9 @@ private:
             resp_buf_[i + 1] = comb[i];
           }
           YGO_SetResponseb(pduel_, resp_buf_);
-        discard_hand_ = false;
           return;
         }
+      }
 
       init_multi_select(min, max, 0, specs);