Incorporate Bedstead into CtsInputMethodTestCases

This changelist also replace the JUnit's Assume.assumeFalse(isAutomotive()) by @RequireNotAutomotive in ImeInsetsVisibilityTest. Bedstead annotations are much easier to query than tests with assumptions in their setUp methods.

Tests are required to add the DeviceState for the annotations to take effect.

Bedstead tests don’t work with JUnit’s AfterClass and BeforeClass, therefore this changelist replace them in both EndToEndImeTestBase an NavigationBarColorTest.

Bug: 356717219
Test: atest -c CtsInputMethodTestCases
Flag: TEST_ONLY
Change-Id: I7154d524af935962db85c936159bc93028493c1b