[6.15.z] Add default content type as yum for make_repository helper

[Satellite-QE]

Cherrypick of PR: #13196

Problem Statement

Changes introduced in #11544 removed the usage of old cli.factory in favor of new cli_factory helpers. And, I've observed a few failures related default content_type missing from hammer repository create command used by make_repository helper, and it was present earlier and missing in cli_factory method.

robottelo.exceptions.CLIFactoryError: Failed to create Repository with data:
{ 'http-proxy-policy': 'none',
  'name': 'sissapUBCf',
  'organization-id': 3,
  'product-id': '1',
  'url': 'http://testserver.example.com:50123/fake_yum0'}
Command "repository create" finished with status 64
stderr contains:
Could not create the repository:
  Missing arguments for '--content-type'.

Solution

Add content_type=yum as default in make_repository helper of cli_factory

Additional Info

#11544 cherrypicking was failed for 6.14.z or older, but it was merged before branching, so this will require cherrypicking to 6.15.z

[Gauravtalreja1]

trigger: test-robottelo
pytest: tests/foreman/cli/test_logging.py::test_positive_logging_from_pulp3 tests/foreman/cli/test_http_proxy.py::test_positive_assign_http_proxy_to_

[jyejare]

@Gauravtalreja1 Looks like you missed the part of a test case name! Please update it !

[Gauravtalreja1]

trigger: test-robottelo
pytest: tests/foreman/cli/test_logging.py::test_positive_logging_from_pulp3 tests/foreman/cli/test_http_proxy.py::test_positive_assign_http_proxy_to_products

[ColeHiggins2]

Ack pending PRT

[Gauravtalreja1]

PRT trying to checkout 6.15.z which isn't available yet, so will merge this as easyfix.