fix horizontal_scrolling()'s incorrect assertions

[SoloSynth1]

Fixes #37 & #39.

The test horizontal_scrolling() does not give enough time for the list to be swiped left. As a result, the test will always fail even when the app is correctly implemented.

This fix adds a wait period (1.5 second) for the scrolling effect to come to a full stop, then check the name on the card on the screen i.e. "Nox".

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