fix: improve swagger Api docunment (#812)

object/storage.go

@@ -56,6 +56,9 @@ func getUploadFileUrl(provider *Provider, fullFilePath string, hasTimestamp bool
 		// provider.Domain = "http://localhost:8000" or "https://door.casdoor.com"
 		host = util.UrlJoin(provider.Domain, "/files")
 	}
+	if provider.Type == "Azure Blob" {
+		host = fmt.Sprintf("%s/%s", host, provider.Bucket)
+	}
 
 	fileUrl := util.UrlJoin(host, objectKey)
 	if hasTimestamp {