[CTS] Fix test CtsInputMethodTestCases Fail

Change the tolerance in this file (cts/tests/inputmethod/mockime/src/com/android/cts/mockime/watermark.java)
from 4 to 6, and then the CTS item can pass

Bug: 233319624
Test: run cts -m CtsInputMethodTestCases -t android.view.inputmethod.cts.InputMethodServiceTest#testImeVisibleAfterRotation
Change-Id: Ib15d13acdd7f5431dd77c2db16dee682c82c1408
1 file changed