fix：添加模版存在性校验

src/SJZY.Track.Application/Services/TrackTemplates/TrackTemplateService.cs

@@ -259,6 +259,11 @@ public class TrackTemplateService : ApplicationService
         #endregion 业务校验
 
         var templateEntity = await _trackTemplateRepository.GetFirstAsync(a => a.Id == input.Id);
+        if (templateEntity == null)
+        {
+            throw new BusinessException(message: "模版不存在");
+        }
+
         ObjectMapper.Map(input, templateEntity);
         var isTrue = await _trackTemplateRepository.UpdateAsync(templateEntity);