double slash (/) in origin url leading to unexpected behaviours

I discovered a bug: https://archive.softwareheritage.org/api/1/origin/https://pypi.org/project/wrld//intrinsic-metadata (note the double '/') fetches the intrinsic metadata but https://archive.softwareheritage.org/api/1/origin/https://pypi.org/project/wrld/intrinsic-metadata returns NotFoundExc error because the origin URL is "https://pypi.org/project/wrld/" (note the / at the end).

I see that there are similar bugs reported (example: #1852 (closed))

I hope these errors are taken care of under #1805

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Migrated from T3123 (view on Phabricator)