[BUG] Re-add tests that require nodes_dn_dynamic_config_enabled

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What is the bug?

In #646 I've removed tests/default/security/api/nodesdn.yaml. These tests don't work without nodes_dn_dynamic_config_enabled. With a corrected schema in that PR they now fail (as they should).

What is the expected behavior?

Re-add the tests with a custom setup and nodes_dn_dynamic_config_enabled enabled.