pytest_plugin: Add support for http request (debian lister related)

Add support for both http and https support. Now a request resolves to a local file in <https?>_, for example:

• http://pypi.org ~> http_pypi.org
• https://files.pythonhosted.org ~> https_files.pythonhosted.org

Related swh-lister#2032 (closed)

Test Plan

tox

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Migrated from D2133 (view on Phabricator)