更新 'PC_Web_Integration_Specification.md'

PC_Web_Integration_Specification.md

@@ -608,7 +608,7 @@ Modify the test machine hosts file, add the following two information
 
 114.80.87.249 api.account.preview.n.xiaomi.net
 
-Test card:
+Test card：
 
 Card number：5123456789012346