Fix API test.

The test project now has more than one installable file, so we can no
longer assume that the first one is the application.

Change-Id: I6059362c691912cafa46caa948d6b22baa9a289e
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>