[Satellite 6.2] Capsule sync fails with error `RPM1004: Error retrieving metadata: NOT FOUND`

Issue

• Capsule sync fails with error RPM1004: Error retrieving metadata: NOT FOUND

• Observed following traceback in the sync log

  Traceback (most recent call last):\n  File \"/usr/lib/python2.7/site-packages/celery/app/trace.py\", line 240, in trace_task\n    R = retval = fun(*args, **kwargs)\n  File \"/usr/lib/python2.7/site-packages/pulp/server/async/tasks.py\", line 473, in __call__\n    return super(Task, self).__call__(*args, **kwargs)\n  File \"/usr/lib/python2.7/site-packages/pulp/server/async/tasks.py\", line 103, in __call__\n    return super(PulpTask, self).__call__(*args, **kwargs)\n  File \"/usr/lib/python2.7/site-packages/celery/app/trace.py\", line 437, in __protected_call__\n    return self.run(*args, **kwargs)\n  File \"/usr/lib/python2.7/site-packages/pulp/server/controllers/repository.py\", line 762, in sync\n    sync_report = sync_repo(transfer_repo, conduit, call_config)\n  File \"/usr/lib/python2.7/site-packages/pulp/server/async/tasks.py\", line 658, in wrap_f\n    return f(*args, **kwargs)\n  File \"/usr/lib/python2.7/site-packages/pulp_rpm/plugins/importers/yum/importer.py\", line 81, in sync_repo\n    report = self._current_sync.run()\n  File \"/usr/lib/python2.7/site-packages/pulp_rpm/plugins/importers/yum/sync.py\", line 320, in run\n    reason=self.repomd_not_found_reason)\nPulpCodedException: Error retrieving metadata: NOT FOUND\n"