Add ns2/managed1.conf to mkeys extra_artifacts

The ns2/managed1.conf file is created by the setup.sh script. Then, in
the tests.sh script it is moved to ns2/managed.conf. The latter file
name is in mkeys extra_artifacts, but the former one is not. This is a
problem when pytest is started with the --setup-only option as it only
runs the setup.sh script (e.g., in the cross-version-config-tests CI
job) and thus failing the "Unexpected files found" assertion.

(cherry picked from commit e7d973bd00)

bin/tests/system/mkeys/tests_sh_mkeys.py

@@ -36,6 +36,7 @@ pytestmark = pytest.mark.extra_artifacts(
         "ns1/root.db.tmp",
         "ns1/zone.key",
         "ns2/managed-keys.bind",
+        "ns2/managed1.conf",
         "ns3/broken.conf",
         "ns3/managed-keys.bind",
         "ns4/nope",