Release 3.6.0 (#239)

* chore: update dependencies

* chore: update user agent for measurements

* chore: we're now at v3.6.0

* chore: update assets

* chore: update bundled CA

* fix: address some goreportcard.com warnings

* fix(debian/changelog): zap release that breaks out build scripts

We're forcing the content of changelog with `dch`, so it's fine to
not have any specific new release in there.

* fix: make sure tests are passing locally

Notably, I removed a chunk of code where we were checking for network
activity. Now we don't fetch the databases and it's not important. Before,
it was important because the databases are ~large.

* fix: temporarily comment out riseupvn integration tests

See https://github.com/ooni/probe/issues/1354 for work aimed at
reducing the rate of false positives (thanks @cyBerta!)

debian/changelog

@@ -1,9 +1,3 @@
-ooniprobe-cli (3.5.2-1) unstable; urgency=medium
-
-  * New release
-
- -- Federico Ceratto <federico@openobservatory.org>  Tue, 16 Feb 2021 12:40:20 +0000
-
 ooniprobe-cli (3.0.9) unstable; urgency=medium
 
   * Test release