avoid using third parties' resources for testing and maybe enable offline testing
testFeedImportAndRemoval uses a third party blog feed for testing.
Maybe, rather use briar's own resources instead of Schneier's blog, e.g. simply supply a static test feed on briarproject's server or use https://code.briarproject.org/briar/briar.atom.
This way of testing will fail when the testing machine is offline, which is not the aim of the test. So, avoiding internet access here might be a better solution and would also support to introduce test cases for feed content that could trip briar functionality.