tests: cleanup unused variable

And I have to add this line here just to make the CI happy, even though
everything is in the first line. Oh well.

Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>

Author: jktjkt

tests/test_context.py

@@ -189,7 +189,7 @@ def get_module_invalid_clb(mod_name, *_):
 
             ctx.external_module_loader.set_module_data_clb(get_module_invalid_clb)
             with self.assertRaises(LibyangError):
-                mod = ctx.load_module("yolo-nodetypes")
+                ctx.load_module("yolo-nodetypes")
 
             ctx.external_module_loader.set_module_data_clb(get_module_valid_clb)
             mod = ctx.load_module("yolo-nodetypes")