Update BrowserAppHelper with button id

The text on negative button was updated "No thanks" -> "No, thanks". Replaced matching by text to matching by button id

Bug: 430191139
Flag: EXEMPT not needed for the funcitonal test
Test: atest TabTearingTest

Change-Id: Ib8eae3d686a82c017258ec4bfaabd8e2c1c9b30a
1 file changed