[6.15.z] [E2E] Recalculate applicability before UI session, fix navigation failure

[Satellite-QE]

Cherrypick of PR: #14095

Problem Statement

• Occasional e2e failure in one or two parameters for UI::Errata::test_end_to_end[rhel7, 8, 9].
• Upon asserting one applicable errata, after installing an outdated applicable package.

tests/foreman/ui/test_errata.py:396: in test_end_to_end
    assert (applicable_errata == 1)
E   AssertionError: Expected 1 applicable errata: RHSA-2012:0055, after setup. Got 0
E   assert 0 == 1

• Follow-up after resolving AssertionError, now failing to navigate to [Details]
  at Ln405: assert session.contenthost.search_content_hosts(...)

navmazing._errors.NavigationTriesExceeded: Navigation failed to reach [Details] in the specified tries
>           raise NoSuchElementException(f"Could not find an element {repr(locator)}") from None
E           selenium.common.exceptions.NoSuchElementException: Message: Could not find an element ".//input[@ng-model='showInstallable']"; For documentation on this error, please visit: ...
../../lib64/python3.11/site-packages/widgetastic/browser.py:467: NoSuchElementException

The page is blank when the test fails, assert does not give the method enough time for a loaded page.
Also put up a very small change for the search_content_hosts() method- Airgun#1240.

Solution

• To resolve applicability, after installing the outdated pkg, we need to manually recalculate errata to show up-to-date applicability in time.
• To resolve navigation, instead of asserting directly on session.contenthost .errata methods, store the method result as a variable, giving time in case the page is slow, UI elements are not loaded yet.
  Then assert upon the variable (typically some sort of response) or expected outcome (generated task(s) etc).

PRT Case

trigger: test-robottelo
pytest: tests/foreman/ui/test_errata.py::test_end_to_end
airgun: 1240

[Satellite-QE]

trigger: test-robottelo
pytest: tests/foreman/ui/test_errata.py::test_end_to_end
airgun: 1240

[Satellite-QE]

PRT Result

Build Number: 5779
Build Status: SUCCESS
PRT Comment: pytest tests/foreman/ui/test_errata.py::test_end_to_end
Test Result : ================= 3 passed, 320 warnings in 2577.27s (0:42:57) =================