chore: content 길이 설정 (WR9-150)

Author: leeys9423

src/main/java/io/crops/warmletter/domain/eventpost/entity/EventComment.java

@@ -22,7 +22,7 @@ public class EventComment extends BaseEntity {
     @Column(nullable = false)
     private Long writerId;
 
-    @Column(nullable = false)
+    @Column(nullable = false, length = 1000)
     private String content;
 
     @Column(nullable = false)