[6.15.z] Errata WIP for remaining UI Failures

[Satellite-QE]

Cherrypick of PR: #15085

Problem Statement

Fix remaining UI errata failures (8-10 in recent CI 6.15.0/stream)

• Fixture improvements
• Remove some remaining outdated setup/ unusable fixtures
• Fix intermittent failures of test_end_to_end and _pagination
• Makes use of api_factory method proposed (closed)
  API-factory: Method to Associate needed entities, then Register the Host #14974

Ongoing Failures

• test_positive_content_host_previous_env: Skipped for now, until BZ #2280882 is resolved.
• test_positive_apply_for_all_hosts: Testing locally Fixed- Airgun PR #1387. Added End2End flag for this case, as it is now very thorough and makes use of multiple install methods.

PRT Case

trigger: test-robottelo
pytest: tests/foreman/ui/test_errata.py
airgun: 1428

[Satellite-QE]

trigger: test-robottelo
pytest: tests/foreman/ui/test_errata.py

[damoore044]

trigger: test-robottelo
pytest: tests/foreman/ui/test_errata.py
airgun: 1428

[Satellite-QE]

PRT Result

Build Number: 7478
Build Status: UNSTABLE
PRT Comment: pytest tests/foreman/ui/test_errata.py --external-logging
Test Result : ===== 2 failed, 15 passed, 1 skipped, 1940 warnings in 5834.74s (1:37:14) ======

[damoore044]

trigger: test-robottelo
pytest: tests/foreman/ui/test_errata.py
airgun: 1428

[Satellite-QE]

PRT Result

Build Number: 7495
Build Status: SUCCESS
PRT Comment: pytest tests/foreman/ui/test_errata.py --external-logging
Test Result : ========== 17 passed, 1 skipped, 2026 warnings in 6384.63s (1:46:24) ===========