Fix inconsistently failing Errata UI, checking New Host > Installed Packages > table

[damoore044]

Purpose

Occasionally see no such element exception for ErrataManagement CI results,
in get_packages() method on view.content.packages.select()
locally it runs without issue, but we should wait for the packages tab to appear before selecting it, after we navigate to the page.

See for prt Robottelo#16814

two tests using this method, New Host UI > Installed Packages tab > read table :

• tests/foreman/ui/test_errata.py:: test_positive_apply_for_all_hosts (upgrade)
• tests/foreman/ui/test_host.py:: test_positive_update_delete_package (rhel8 only) Fails in setup

Related Issue (seen occasionally in 6.15, 6.16 el8/9)

Error Message
selenium.common.exceptions.NoSuchElementException: Message: Could not find an element Locator(by='xpath', locator='.//div[contains(@class, "pf-c-tabs")]/ul/li[button[normalize-space(.)="Content"]]'); 

Stacktrace
tests/foreman/ui/test_errata.py:947: in test_positive_apply_for_all_hosts
    updated_pkg = session.host_new.get_packages(
../../lib64/python3.12/site-packages/airgun/entities/host_new.py:334: in get_packages
    view.content.packages.select()
../../lib64/python3.12/site-packages/widgetastic/widget/base.py:146: in __get__
    obj.child_widget_accessed(widget)
   
    ...
E   selenium.common.exceptions.NoSuchElementException: Message: Could not find an element Locator(by='xpath', locator='.//div[contains(@class, "pf-c-tabs")]/ul/li[button[normalize-space(.)="Content"]]');