Fixed the bug that add new tag was not valid for the first time

modules/blogging/src/Volo.Blogging.Application/Volo/Blogging/Posts/PostAppService.cs

@@ -228,8 +228,9 @@ namespace Volo.Blogging.Posts
                 {
                     tag.IncreaseUsageCount();
                     tag = await _tagRepository.UpdateAsync(tag);
-                    post.AddTag(tag.Id);
                 }
+
+                post.AddTag(tag.Id);
             }
         }