tracker-extract: Avoid the fluiddec gstreamer plugin

This is a module that attempts to decode MIDI and send it to the
soundcard. We don't want such access triggered from tracker-extract
(and it's actually caught by our seccomp sandbox). Avoid this plugin
altogether.

Fixes: #101
3 jobs for wip/carlosg/ignore-fluiddec-plugin in 5 minutes and 48 seconds (queued for 1 second)
Status Name Job ID Coverage
  Test
passed test-fedora-latest #936634

00:01:21

passed test-ubuntu-rolling #936635

00:01:54

 
  Analysis
passed coverage-analysis #936636

00:03:53

49.7%