loupe: don't pass args to download_testdata

You can see what these args are trying to do, but the function
does not currently work that way. I think running it without
args should get what the test wants. If Lukas wants to refine
download_testdata so you can specify the payload and where to
extract it, he can do that, then put this back...

Signed-off-by: Adam Williamson <awilliam@redhat.com>

tests/applications/loupe/aaa_setup.pm

@@ -13,7 +13,7 @@ sub run {
     # Perform git test
     check_and_install_git();
     # Download the test data
-    download_testdata("eog", "Pictures");
+    download_testdata();
     # Exit the terminal
     desktop_vt;