Set slug by default to true. (#3434)
Set slug by default to true. (#3434)

This is gonna be released in September in a new major release.

https://www.sitespeed.io/documentation/sitespeed.io/graphite/#upgrade-to-use-the-test-slug-in-the-namespace
sitespeedio/sitespeed.io,sitespeedio/sitespeed.io,sitespeedio/sitespeed.io,sitespeedio/sitespeed.io