fixup! Add support for --nest=... --hosts=cache://...

conftest.py

@@ -200,15 +200,13 @@ def _cleanup_hosts():
     try:
         host_list = [setup_host(hostname_or_ip, config=pytestconfig)
                      for hostname_or_ip in hostname_list]
-    except Exception:
-        _cleanup_hosts()
-        raise
 
-    if not host_list:
-        pytest.fail("This test requires at least one --hosts parameter")
-    yield host_list
+        if not host_list:
+            pytest.fail("This test requires at least one --hosts parameter")
+        yield host_list
 
-    _cleanup_hosts
+    finally:
+        _cleanup_hosts
 
 @pytest.fixture(scope='session')
 def registered_xo_cli():