Fix instrumentation link in README (prometheus#384)

zhulongcheng · brian-brazil · commit 2206f15991e0 · 2019-03-15T10:13:41.000Z
Signed-off-by: zhulongcheng &lt;zhulongcheng.me@gmail.com&gt;
diff --git a/README.md b/README.md
@@ -57,7 +57,7 @@ This package can be found on
 
 Four types of metric are offered: Counter, Gauge, Summary and Histogram.
 See the documentation on [metric types](http://prometheus.io/docs/concepts/metric_types/)
-and [instrumentation best practices](http://prometheus.io/docs/practices/instrumentation/#counter-vs.-gauge,-summary-vs.-histogram)
+and [instrumentation best practices](https://prometheus.io/docs/practices/instrumentation/#counter-vs-gauge-summary-vs-histogram)
 on how to use them.
 
 ### Counter
