Pastrami Egg Rolls

Name: Pastrami Egg Rolls
Ingredients: 1 tablespoon olive oil; 1 small onion, finely chopped; 1 stalk celery, finely chopped; Pinch kosher salt; 4 cloves garlic, minced; 1 teaspoon caraway seeds; 8 ounces pastrami, finely sliced; 10 ounces shredded green cabbageor coleslaw mix; 1 tablespoon soy sauce; 1 tablespoon apple cider vinegar; Freshly ground black pepper, to taste; 1 tablespoon all-purpose flour; 8 eggroll wrappers; Canola oil, for frying; Strong deli mustard or Chinese hot mustard, for serving