修改用户管理复选框宽度，防止部分浏览器出现省略号

ruoyi-ui/src/views/system/user/index.vue

@@ -133,7 +133,7 @@
         </el-row>
 
         <el-table v-loading="loading" :data="userList" @selection-change="handleSelectionChange">
-          <el-table-column type="selection" width="40" align="center" />
+          <el-table-column type="selection" width="50" align="center" />
           <el-table-column label="用户编号" align="center" prop="userId" />
           <el-table-column label="用户名称" align="center" prop="userName" :show-overflow-tooltip="true" />
           <el-table-column label="用户昵称" align="center" prop="nickName" :show-overflow-tooltip="true" />