Bug Report - Duplicate 'http://' in RestMetricsFetcher

[kr11]

🐛 Describe the bug

There seem a bug of URL formatted concatenation in RestMetricsFetcher. As following codes, when FetchPodMetrics calls FetchMetric, url may contain a duplicate "http://" prefix.

// aibrix/pkg/controller/podautoscaler/metrics/fetcher.go
func (f *RestMetricsFetcher) FetchPodMetrics(ctx context.Context, pod v1.Pod, metricsPort int, metricName string) (float64, error) {
        // pass into "http://{PodIP}:{Port}", 
	return f.FetchMetric(ctx, fmt.Sprintf("http://%s:%d", pod.Status.PodIP, metricsPort), "/metrics", metricName)
}

func (f *RestMetricsFetcher) FetchMetric(ctx context.Context, endpoint string, path string, metricName string) (float64, error) {
	// HERE. url will be like "http://http://{PodIP}:{Port}/metrics", 
	url := fmt.Sprintf("http://%s/%s", strings.TrimRight(endpoint, "/"), strings.TrimLeft(path, "/"))
    // blablabla
}

Steps to Reproduce

No response

Expected behavior

No response

Environment

No response

[kr11]

@zhangjyr please help to double check it.