add new type: Concurrent

Author: peanut996

lib/i18n.tsx

@@ -220,6 +220,7 @@ const translations = {
     'category.Kafka': 'Kafka',
     'category.Java': 'Java',
     'category.ThreadPool': 'Thread Pool',
+    'category.Concurrent': 'Concurrent',
     'category.OperationSystem': 'Operation System',
     'category.SystemDesign': 'System Design',
     'category.HTML': 'HTML',
@@ -486,6 +487,7 @@ const translations = {
     'category.Kafka': 'Kafka',
     'category.Java': 'Java',
     'category.ThreadPool': '线程池',
+    'category.Concurrent': '并发',
     'category.OperationSystem': '操作系统',
     'category.SystemDesign': '系统设计',
     'category.HTML': 'HTML',

lib/types.ts

@@ -63,6 +63,7 @@ export enum QuestionCategory {
   Java = 'Java',
   JVM = 'JVM',
   ThreadPool = 'Thread Pool',
+  Concurrent = 'Concurrent',
   OperationSystem = 'Operation System',
   SystemDesign = 'System Design',