Description of problem:

Now that Satellite is in SCA mode by default. We should also update the endpoint "GET /katello/api/activation_keys/:id/product_content" so users do not have to pass in the content_access_mode_all param as TRUE. If users do not use this param, an empty list is returned

Version-Release number of selected component (if applicable): 6.16.0

How reproducible:100%

Steps to Reproduce:
1. Create Organization
2. Sync RedHat Repository
3. Enable RedHat Repository on Activation key
4. Hit GET /katello/api/activation_keys/:id/product_content endpoint or run

hammer activation-key product-content --id --organization-id

with and without the --content-access-mode-all param

Actual results:

Without adding the --content-access-mode-all param, an empty list is returned

With adding the --content-access-mode-all param, the added repository is shown

Expected results:

We should see the enabled repositories on the activation key without needed to pass this param in since sca is now the default

Additional info:

DEV Tracker for https://issues.redhat.com/browse/SAT-24526
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2274388