test(core): do not use internal MP4 muxer

Author: ThibaultBee

core/src/androidTest/java/io/github/thibaultbee/streampack/core/streamer/dual/file/CameraDualStreamerFileTest.kt

@@ -166,7 +166,7 @@ class CameraDualStreamerFileTest(
                     null,
                     UriMediaDescriptor(FileUtils.createCacheFile("video.mp4").toUri()),
                     true,
-                    CompositeEndpointFactory(Mp4Muxer(), FileSink())
+                    null
                 ),
             )
         }