Add automated test for "Create a AWM application in a nested document"

The manual test is here: Create a AWM application in a nested document

Existing automated coverage

• WizardIT#createApplication: Full wizard as a simple user: location picked with the tree in a 2-level nested space, name, field drag and drop, template provider icon/description, description, live table column, Finish; asserts the home page, adding entries, the breadcrumb path, the AWM apps live table, and Delete Application
• ApplicationsPanelEntryIT#applicationPanelEntry: Sets the app title and icon on the application home edit form (not through the wizard), asserts they are kept, and opens the app by clicking its title in the Applications panel (icon not asserted in the panel)
• NavigationPanelIT#verifyPanelCaching: Creates a top-level AWM app and asserts it is EXCLUDED from the Navigation panel (the opposite of the manual expectation; no nested app is looked up in the tree)

Missing automated coverage

• Create pages a, a/b and a/b/c (via URL/REST)
• Start the wizard from the Applications panel: More applications > Create your own! > Create Application
• Type the location a.b.c manually in the location picker (not only via the tree) and set an application name
• Go through the fields, description and live table columns steps, pick an icon and click Finish
• Assert the application home page is at a/b/c/<appName> (breadcrumb / page reference)
• Assert the application is listed in the Applications panel with its icon and opening it leads to a/b/c/<appName>
• Assert the Navigation panel tree contains the app under a > b > c

Suggested location: xwiki-platform-core/xwiki-platform-appwithinminutes/xwiki-platform-appwithinminutes-test/xwiki-platform-appwithinminutes-test-docker/src/test/it/org/xwiki/appwithinminutes/test/ui/WizardIT.java

Found by comparing the XWiki 18.4.4 manual test runs against the automated tests on master (a0055f10a1a).