[PM] Add PackageInstaller CUJ test case (34/N)

Add CtsPackageInstallerCUJDeviceAdminTestCases and
CtsPackageInstallerCUJMultiUsersTestCases into postsubmit in
TEST_MAPPING

Flag: TEST_ONLY
Bug: 332323134
Test: atest -p frameworks/base/core/java/android/content/pm/TEST_MAPPING:postsubmit
Test: atest -p frameworks/base/services/core/java/com/android/server/pm/TEST_MAPPING:postsubmit
Test: atest -p frameworks/base/packages/PackageInstaller/TEST_MAPPING:postsubmit
Change-Id: I9b68ff1b05c6a4c8ac0db27c20f8aa5cb21ceb64