use_json_scraper configuration doesn't work for most of fallback repo

[superma58]

The configuration pypi.use_json_scraper says it requires the fallback repo has /json endpoints. But the code write: url = "%s/pypi/%s/json/" % (self.base_index, project_name) at locator.py. I think it should remove the last slash.

[stevearc]

Thanks for the report! It looks like pypi.org was doing a redirect so the trailing slash was still working. Was there another situation where the trailing slash was causing it to break?