Description of problem:
When configuring Network Sync from the Satellite WebUI > Subscriptions > Manage Manifest > CDN Configuration, if the source Satellite does not contain the same repositories as the requesting server the operation fails.
Could it be presented to the user to choose which repositories they would like to choose from that match the source from the requesting Satellite?

Version-Release number of selected component (if applicable):
6.12

How reproducible:
Every time

Steps to Reproduce:
1.On source satellite enable 1 repo
2.On requesting Satellite, add 2 repos
3.Configure network sync on the requesting satellite to the source satellite

Actual results:
Operation fails, nothing changes.

Expected results:
A list of matching repositories is presented for the user to choose from.

Additional info: