Test that SVG conversion maintain transparency

Author: nicolasbeauvais

tests/Conversions/ImageGenerators/SvgTest.php

@@ -18,4 +18,6 @@
     $imageFile = $imageGenerator->convert($media->getPath());
 
     expect(mime_content_type($imageFile))->toEqual('image/png');
+
+    expect((new Imagick($imageFile))->getImageAlphaChannel())->toBeTrue();
 })->skipWhenRunningLocally();