RPM Support

Similar to https://pulp.plan.io/issues/5655

The fix seems to only have been a partial fix and does not handle trailing slashes when downloading kickstart trees.

My repository has a url of https://cdn.redhat.com/content/dist/rhel/server/7/7.7/x86_64/kickstart/

but after syncing, i have no distribution files downloaded and in my logs i see:

Nov  7 15:56:55 devel rq: pulp: pulp_rpm.app.tasks.synchronizing:INFO: Synchronizing: repository=Red_Hat_Enterprise_Linux_7_Server_Kickstart_x86_64_7_7-83744 remote=Red_Hat_Enterprise_Linux_7_Server_Kickstart_x86_64_7_7-88753
Nov  7 15:56:56 devel rq: Giving up _run(...) after 1 tries (aiohttp.client_exceptions.ClientResponseError: 404, message='Not Found', url=URL('https://cdn.redhat.com/content/dist/rhel/server/7/7.7/x86_64/.treeinfo'))
Nov  7 15:56:56 devel rq: pulp: backoff:ERROR: Giving up _run(...) after 1 tries (aiohttp.client_exceptions.ClientResponseError: 404, message='Not Found', url=URL('https://cdn.redhat.com/content/dist/rhel/server/7/7.7/x86_64/.treeinfo'))
Nov  7 15:56:56 devel rq: Giving up _run(...) after 1 tries (aiohttp.client_exceptions.ClientResponseError: 404, message='Not Found', url=URL('https://cdn.redhat.com/content/dist/rhel/server/7/7.7/x86_64/treeinfo'))
Nov  7 15:56:56 devel rq: pulp: backoff:ERROR: Giving up _run(...) after 1 tries (aiohttp.client_exceptions.ClientResponseError: 404, message='Not Found', url=URL('https://cdn.redhat.com/content/dist/rhel/server/7/7.7/x86_64/treeinfo'))