message: Apply Mark's fix to fix a sync test
diff: @@ -196,8 +196,10 @@ TEST_CASE("SyncSession: management by SyncUser", "[sync]") {
  REQUIRE(on_disk_path.size() > 0);
  REQUIRE(weak_session.lock());
  }
  - // Session is dead, so the SyncUser's weak pointer to it should be nulled out.
  - REQUIRE(weak_session.expired());
  + // Wait for the session to die. It may not happen immediately if a progress or error handler
  + // is called on a background thread and keeps the session alive past the scope of the above block.
  + EventLoop::main().run_until([&] { return weak_session.expired(); });
  +
  // The next time we request it, it'll be created anew.
  // The call to `get_session()` should result in `SyncUser::register_session()` being called.
  auto session = SyncManager::shared().get_session(on_disk_path, config);
  