Add aiida_profile_clean to test_devel.py

Without it, the `localhost` computer would have already been created in
the tests for `launch-add`, so the first test for `launch-multiply-add`
would fail.

tests/cmdline/commands/test_devel.py

@@ -23,6 +23,7 @@ def test_run_sql(run_cli_command):
     assert str(Node.collection.count()) in result.output, result.output
 
 
+@pytest.mark.usefixtures('aiida_profile_clean')
 def test_launch_add(run_cli_command):
     """Test ``verdi devel launch-add``.
 
@@ -58,6 +59,7 @@ def test_launch_add_code(run_cli_command, aiida_code_installed):
     assert node.is_finished_ok
 
 
+@pytest.mark.usefixtures('aiida_profile_clean')
 def test_launch_multiply_add(run_cli_command):
     """Test ``verdi devel launch-multiply-add``.