Fix unselected topic prompt exception

Author: shuzijun

src/main/java/com/shuzijun/leetcode/plugin/manager/ViewManager.java

@@ -208,7 +208,7 @@ public static Question getTreeQuestion(JTree tree,Project project) {
             }
         }
         if (question == null) {
-            MessageUtils.getInstance(project).showInfoMsg("info", PropertiesUtils.getInfo("response.select"));
+            MessageUtils.getInstance(project).showInfoMsg("info", PropertiesUtils.getInfo("tree.select"));
         }
         return question;
     }

src/main/resources/i18n/info.properties

@@ -34,4 +34,5 @@ updata=Leetcode Editor new version {0} is found. Please update the plugin
 user.email=YOU HAVE NOT VERIFIED YOUR ACCOUNT\nYou cannot submit your code to the judge system until you verify your email.\nYou may resend the verification email or change your email in your profile page.
 template.variable=${0}question.title{1}\tquestion title\tex:Two Sum\n${0}question.titleSlug{1}\tquestion title slug \tex:two-sum\n${0}question.frontendQuestionId{1}\tquestion serial number\n${0}question.content{1}\tquestion content\n${0}question.code{1}\tquestion code\n$!velocityTool.camelCaseName(str)\ttransform str camel case
 tree.load=Please load questions first
-tree.null=Questions returned are empty
+tree.null=Questions returned are empty
+tree.select=Please select a valid question in the list

src/main/resources/i18n/info_zh.properties

@@ -34,4 +34,5 @@ updata=leetcode editor\u65B0\u7248\u672C {0} \u53D1\u5E03,\u8BF7\u53CA\u65F6\u66
 user.email=\u60A8\u5C1A\u672A\u9A8C\u8BC1\u81EA\u5DF1\u7684\u5E10\u6237\n\u5728\u9A8C\u8BC1\u7535\u5B50\u90AE\u4EF6\u4E4B\u524D\uFF0C\u60A8\u65E0\u6CD5\u5C06\u4EE3\u7801\u63D0\u4EA4\u7ED9\u8BC4\u5224\u7CFB\u7EDF\u3002\n\u60A8\u53EF\u4EE5\u5728\u4E2A\u4EBA\u8D44\u6599\u9875\u9762\u4E2D\u91CD\u65B0\u53D1\u9001\u9A8C\u8BC1\u7535\u5B50\u90AE\u4EF6\u6216\u66F4\u6539\u7535\u5B50\u90AE\u4EF6\u3002
 template.variable=${0}question.title{1}\t\u9898\u76EE\u6807\u9898\t\u793A\u4F8B:\u4E24\u6570\u4E4B\u548C\n${0}question.titleSlug{1}\t\u9898\u76EE\u6807\u8BB0\t\u793A\u4F8B:two-sum\n${0}question.frontendQuestionId{1}\t\u9898\u76EE\u7F16\u53F7\n${0}question.content{1}\t\u9898\u76EE\u63CF\u8FF0\n${0}question.code{1}\t\u9898\u76EE\u4EE3\u7801\n$!velocityTool.camelCaseName(str)\t\u8F6C\u6362\u5B57\u7B26\u4E3A\u9A7C\u5CF0\u6837\u5F0F
 tree.load=\u8BF7\u5148\u52A0\u8F7D\u9898\u76EE
-tree.null=\u83B7\u53D6\u9898\u76EE\u4E3A\u7A7A
+tree.null=\u83B7\u53D6\u9898\u76EE\u4E3A\u7A7A
+tree.select=\u8BF7\u5728\u5217\u8868\u4E2D\u9009\u62E9\u4E00\u4E2A\u6709\u6548\u7684\u9898\u76EE