gh-137463: Update `validate_abstract_methods` in `test_collections.py` (#137464)

Update `validate_abstract_methods` in `test_collections.py`

The test for missing abstract methods in `validate_abstract_methods` incorrectly attempted to instantiate the generated class `C` with an argument (`C(name)`), which always raises a `TypeError: C() takes no arguments`. Although the test originally passes, it passes for the wrong reason.

This change makes the test correctly validate the enforcement of abstract methods in ABCs.