Refine split screen app orientation request  tests

In both split screen orientation requests test, it should check
device is portrait or landscape default then set initial rotation
value.

Besides, change rotation set call after split active to enhance
tests stability because it will afect by home rotation setting.
This change would not affect the behavior we want to check and test.

Bug: 194158966
Test: atest AppConfigurationTests
Change-Id: Id7b7343b7d7993b6cffe3b656f602d78aea361af
1 file changed