0335: Telemetry Coverage endpoint

let's just coverage-our-ass on this one

While I don't mind telemetry (development needs meaningful feedback to better the product), and I trust the data is not PII, and/or anonymized into buckets etc (you can check this you know), and I understand this one needs to be outside the Telemetry pref in order to gather the one-time ping ... and I trust Mozilla's motives ... I'm starting to get a little annoyed at the non-stop incessant increasing telemetry bullshittery and ass-fuckery around sending data home, and the lengths some Mozilla devs will go to, to hide this info (hidden prefs, access denied tickets to hide discussion of what should be public, and even **not even adhering to their own documentation**).

I will also be killing as many Activity Stream endpoints as well - as long as they are in line with our js - pocket, snippets, onboarding etc. And I will add those from personal as inactive for end-users - eg cfr

user.js

@@ -234,6 +234,7 @@ user_pref("datareporting.healthreport.uploadEnabled", false);
 user_pref("datareporting.policy.dataSubmissionEnabled", false);
 /* 0335: disable Telemetry Coverage [FF64+]
  * [1] https://blog.mozilla.org/data/2018/08/20/effectively-measuring-search-in-firefox/ ***/
+user_pref("toolkit.coverage.endpoint.base", "");
 user_pref("toolkit.coverage.opt-out", true); // [HIDDEN PREF]
 /* 0350: disable crash reports ***/
 user_pref("breakpad.reportURL", "");