EZEE-2181: Improve UDW branch switching

[mnocon]

Question	Answer
Tickets	https://jira.ez.no/browse/EZEE-2181
Bug fix?	no
New feature?	no
BC breaks?	no
Tests pass?	yes
Doc needed?	no
License	GPL-2.0

This fix is required for Page Builder, otherwise the tests will be failing soon 😢

Problem

What happens:
in Collection Block scenario, the following items are picked (one after another): 'Home,Home/eZ Platform,Media/Images`.

Sometimes it fails when trying to select the last item: I believe it's because we have to switch the parent UDW path (from Home to Media), but for a brief moment before the switch is done the Home items are still displayed. So, in a timeline:

1. Home is selected (Home items are displayed)
2. Media is clicked
3. Before Media items are loaded Home items are still displayed
4. Media items are displayed

(example: http://recordit.co/yPeHbBf4Xl)

If Behat tries to interact with the displayed elements in Phase 3, it won't find the searched element by text and the tests will fail.

Potential solution

This PR tries to counteract this behaviour by waiting until the loading spinner in UDW disappears. It works locally, I didn't have time to setup this PR as a dependency in Page Builder.

• Other solution: wrap getElementByText with waitUntil and wait until it succeeds.

Checklist:

• Coding standards ($ composer fix-cs)
• Ready for Code Review

[m-tyrala]

👍