Add Support for Cache and S3 related metrics in Prometheus endpoint (#8591)

This PR adds support below metrics

- Cache Hit Count
- Cache Miss Count
- Data served from Cache (in Bytes)
- Bytes received from AWS S3
- Bytes sent to AWS S3
- Number of requests sent to AWS S3

Fixes #8549

cmd/disk-usage.go

@@ -34,7 +34,7 @@ func walk(ctx context.Context, path string, usageFn usageFunc) error {
 		return err
 	}
 
-	if !hasSuffix(path, SlashSeparator) {
+	if !HasSuffix(path, SlashSeparator) {
 		return nil
 	}