Update doc comment
Update doc comment

This should have gone into a previous commit, but I forgot to save
this particular file.

keegancsmith/prometheus,dmilstein/prometheus,kangwoo/prometheus,Conorbro/prometheus,AlekSi/prometheus,tomwilkie/prometheus,datajet-io/prometheus,agaoglu/prometheus,prometheus/prometheus,tomwilkie/prometheus,AlekSi/prometheus,Conorbro/prometheus,eliothedeman/prometheus,kzittritsch/prometheus,kzittritsch/prometheus,eliothedeman/prometheus,adamron1/prometheus,dsymonds/prometheus,adamron1/prometheus,JavierZunzunegui/prometheus,dmilstein/prometheus,adamron1/prometheus,keegancsmith/prometheus,alileza/prometheus,keegancsmith/prometheus,SaltedMan/prometheus-annotated,sudhi-vm/prometheus,gottwald/prometheus,AlekSi/prometheus,sudhi-vm/prometheus,dsymonds/prometheus,tomwilkie/prometheus,Gouthamve/prometheus,agaoglu/prometheus,msiebuhr/prometheus,agaoglu/prometheus,tattsun/prometheus,yanghongkjxy/prometheus,gottwald/prometheus,gottwald/prometheus,alileza/prometheus,amorken/prometheus,sudhi-vm/prometheus,slok/prometheus,brancz/prometheus,alileza/prometheus,Colstuwjx/prometheus,keegancsmith/prometheus,ton31337/prometheus,PrFalken/prometheus,JavierZunzunegui/prometheus,tomwilkie/prometheus,brancz/prometheus,GoogleCloudPlatform/prometheus,dmilstein/prometheus,Colstuwjx/prometheus,slok/prometheus,amorken/prometheus,brancz/prometheus,Conorbro/prometheus,tattsun/prometheus,prometheus/prometheus,AlekSi/prometheus,gottwald/prometheus,alileza/prometheus,yanghongkjxy/prometheus,agaoglu/prometheus,msiebuhr/prometheus,yanghongkjxy/prometheus,kangwoo/prometheus,kangwoo/prometheus,Stackdriver/stackdriver-prometheus,sudhi-vm/prometheus,Colstuwjx/prometheus,Gouthamve/prometheus,adamron1/prometheus,slok/prometheus,amorken/prometheus,alileza/prometheus,Stackdriver/stackdriver-prometheus,JavierZunzunegui/prometheus,prometheus/prometheus,eliothedeman/prometheus,kzittritsch/prometheus,PrFalken/prometheus,prometheus/prometheus,GoogleCloudPlatform/prometheus,Gouthamve/prometheus,tattsun/prometheus,dmilstein/prometheus,eliothedeman/prometheus,ton31337/prometheus,Conorbro/prometheus,datajet-io/prometheus,prometheus/prometheus,Stackdriver/stackdriver-prometheus,Gouthamve/prometheus,PrFalken/prometheus,ton31337/prometheus,ton31337/prometheus,PrFalken/prometheus,amorken/prometheus,brancz/prometheus,kzittritsch/prometheus,dsymonds/prometheus,kangwoo/prometheus,keegancsmith/prometheus,Colstuwjx/prometheus,Stackdriver/stackdriver-prometheus,GoogleCloudPlatform/prometheus,datajet-io/prometheus,SaltedMan/prometheus-annotated,dsymonds/prometheus,GoogleCloudPlatform/prometheus,SaltedMan/prometheus-annotated,msiebuhr/prometheus,tattsun/prometheus,yanghongkjxy/prometheus,msiebuhr/prometheus,datajet-io/prometheus,slok/prometheus,GoogleCloudPlatform/prometheus,SaltedMan/prometheus-annotated,JavierZunzunegui/prometheus