chore: replace all cn comments to en version by volc api (#313)

backend/domain/memory/variables/service/variables_impl.go

@@ -133,7 +133,7 @@ func (*variablesImpl) mergeVariableList(_ context.Context, sysVarsList, variable
 		mergedMap[sysVar.Keyword] = sysVar
 	}
 
-	// 可以覆盖 sysVar
+	// Can overwrite sysVar
 	for _, variable := range variablesList {
 		mergedMap[variable.Keyword] = variable
 	}
@@ -420,7 +420,7 @@ func (v *variablesImpl) sortKVItem(items []*kvmemory.KVItem, meta *entity.Variab
 		i := items[ii]
 		j := items[jj]
 
-		// 如果都是系统变量，这里不需要变换位置
+		// If they are all system variables, there is no need to change positions here
 		if i.IsSystem && !j.IsSystem {
 			return false
 		}