Make kis_animation_importer_test a KISTEST_MAIN test

This allows it to start, however, the test is faulty since we
get a safe assert now:

QFATAL : KisAnimationImporterTest::testImport() SAFE ASSERT (krita): "!sanityCheckPointer.isValid()" in file /home/boud/dev/krita/libs/ui/KisDocument.cpp, line 501