[modify] #24 menu entity의 name field 길이 수정

src/main/java/com/posomo/saltit/domain/restaurant/entity/RestaurantMenu.java

@@ -18,7 +18,7 @@ public class RestaurantMenu{
     @JoinColumn(name = "restaurant_id")
     @ManyToOne
     private Restaurant restaurant;
-    @Column(length = 20)
+    @Column(length = 300)
     private String name;
     private Integer price;
     private Integer orderNumber;