Merge branch '62971-embed-specific-metrics-chart-in-issue-docs' into 'master'

Embed specific metrics chart in issue docs

See merge request gitlab-org/gitlab-ce!31900

doc/user/project/integrations/prometheus.md

@@ -363,6 +363,10 @@ It is possible to display metrics charts within [GitLab Flavored Markdown](../..
 
 To display a metric chart, include a link of the form `https://<root_url>/<project>/environments/<environment_id>/metrics`.
 
+A single chart may also be embedded. You can generate a link to the chart via the dropdown located on the right side of the chart:  
+
+![Generate Link To Chart](img/generate_link_to_chart.png)
+
 The following requirements must be met for the metric to unfurl:
 
 - The `<environment_id>` must correspond to a real environment.