tests: 'showingCardHidesFullScreen' - flaky

Seen on Ubuntu and Windows

Likely cause:

* https://redirect.github.com/ankidroid/Anki-Android/pull/15728
* ~ 35f475f

AnkiDroid/src/test/java/com/ichi2/anki/ReviewerNoParamTest.kt

@@ -133,6 +133,12 @@ class ReviewerNoParamTest : RobolectricTest() {
     }
 
     @Test
+    @Flaky(
+        OS.ALL,
+        "Hide should be called after answering a card" +
+            "    Expected: a value greater than <2>" +
+            "         but: <2> was equal to <2>"
+    )
     fun showingCardHidesFullScreen() {
         addNoteUsingBasicModel("Hello", "World")
         val reviewer = startReviewerFullScreen()