re-add player's own dbus name

Author: vixalien

build-aux/flatpak/com.vixalien.decibels.json

@@ -22,7 +22,8 @@
     "--socket=fallback-x11",
     "--socket=wayland",
     "--socket=pulseaudio",
-    "--env=GJS_DISABLE_JIT=1"
+    "--env=GJS_DISABLE_JIT=1",
+    "--own-name=org.mpris.MediaPlayer2.Decibels"
   ],
   "cleanup": [
     "/include",