* Tests: add a test for worlds to only modify the itempool in `create_items`
* extend test multiworld setup instead of a new function
* cleanup the test a bit
* put more strict wording in `create_items` docstring
* list of shame
* Don't call `set_rules` before testing
* remove ChecksFinder from the list of shame
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Co-authored-by: black-sliver <59490463+black-sliver@users.noreply.github.com>
Co-authored-by: Fabian Dill <Berserker66@users.noreply.github.com>