Run gst-indent through the files

This is required before we enabled an indent test in the CI.

https://gitlab.freedesktop.org/gstreamer/gstreamer-project/issues/33

examples/c/play_timeline_with_one_clip.c

@@ -27,7 +27,7 @@ main (int argc, char **argv)
 
     if (clip == NULL) {
       g_printerr ("%s can not be used, make sure it is a supported media file",
-              argv[1]);
+          argv[1]);
 
       return 1;
     }