Unable to test if mod_pagespeed is enabled via CLI #12024

While testing https://github.com/piwik/piwik/pull/12019 I noticed I get the error

INFO [2017-09-08 12:16:39] Unable to test if mod_pagespeed is enabled: the request to http://unknown/./console?module=Installation&action=getEmptyPageForSystemCheck failed

when executing ./console diagnostics:run

I searched for similar issues but they seem different. Seems like Url::getCurrentUrlWithoutQueryString() does not return a URL.

Might be better to use SettingsPiwik::getPiwikUrl() or so

Bug still exists in 4.5

I confirm, bug still exist on Matomo 4.5

Bug exists still

Let's use SettingsPiwik::getPiwikUrl() and if we don't get a URL from this method then we just skip this test.