hammer import content-host fails with repository conflict errors

Issue

• Migrating Satellite 5.6 data to Satellite 6 instance fails during system profile migration to content-hosts.

# hammer import content-host --csv-file /tmp/exports/system-profiles.csv  --export-directory /root/contenthosts

• Foreman production.log shows messages like below,

foreman/production.log examples:
ActiveRecord::RecordInvalid
base: ["Repository conflict: 'Red Hat Enterprise Linux 6 Server - Supplementary RPMs x86_64 6Server' is in ."]
Completed 422 Unprocessable Entity in 111ms (Views: 0.3ms | ActiveRecord: 8.1ms)
ActiveRecord::RecordInvalid
base: ["Repository conflict: 'Red Hat Enterprise Linux 7 Server - Optional RPMs x86_64 7Server' is in ."]
Completed 422 Unprocessable Entity in 88ms (Views: 0.3ms | ActiveRecord: 7.0ms)
ActiveRecord::RecordInvalid
base: ["Repository conflict: 'Red Hat Enterprise Linux 5 Server - Supplementary RPMs i386 5Server' is in ."]
Completed 422 Unprocessable Entity in 304ms (Views: 0.3ms | ActiveRecord: 10.0ms)