As a user, I can specify `headers` as an option for all remote types
For RPM content, oracle linux needs headers sent for the server to respond properly. You can see this work started in these PR: https://github.com/pulp/pulpcore/pull/1041 and https://github.com/pulp/pulp_rpm/pull/1896/
For syncing content using Alternate Content Sources from Pulp instances in EC2, e.g. RHUI servers it also requires headers to be sent with downloads.
That means on
Remote the new field would be:
headers = models.JsonField(null=True)