Added strict_mode: false to android.bp for the robolectric tests

The robolectric tests were failing because isRobolecticTest() references
android.os.Build which is injected as part of the Robolectric environment,
unforatunately, after the Rule is instantiated, which causes the test to
fail.  Turning off strict_mode in Android.bp works around this.

Bug: 334089788
Flag: TEST_ONLY
Test: tested manually with atest
Change-Id: Iac7486e82a801600a84d4f17854f97cc3bedd99b