Fix Text tests (facebook#48279)

Summary:
Pull Request resolved: facebook#48279

The text tests has 2 issues:
* on iOS, the Text cell was sometimes rendered below the tabbar, with a small percentage visible. When this happens, the test was actually moving to a different tab rather then navigating to the Text screen
* on Android, sometimes navigation took too long and a scroll command was issued. This moved the screen away from the right screen we wanted to test.

This change fixes both issues by ensuring that the Text cell is 100% visible (not behind the tabbar) and by ensuring that the title "Text" is visible in Android, so the navigatin has actually happened

## Changelog:
[Internal] - Fix Text tests

Reviewed By: fabriziocucci

Differential Revision: D67274009

fbshipit-source-id: ed12f096788e7e6e74ee8d336dba350b35b85e81

packages/rn-tester/.maestro/text.yml

@@ -7,13 +7,17 @@ appId: ${APP_ID} # iOS: com.meta.RNTester.localDevelopment | Android: com.facebo
       id: "Text"
     direction: DOWN
     speed: 60
+    timeout: 60000 #ms
+    visibilityPercentage: 100
 - tapOn:
     id: "Text"
+- assertVisible: "Text"
 - scrollUntilVisible:
     element:
       id: "background-border-width"
     direction: DOWN
-    speed: 10
+    speed: 20
+    timeout: 60000 #ms
     visibilityPercentage: 100
 - assertVisible: "Text with background color only"
 - assertVisible: "Text with background color and uniform borderRadii"