Hiding create_bed prop

For now

sound_objects/operator_adm_export.py

@@ -38,7 +38,8 @@ class ADMWaveExport(Operator, ExportHelper):
     create_bed: BoolProperty(
         name="Create 7.1 Bed",
         description="Create a bed for all sounds not included on object tracks",
-        default=False
+        default=False,
+        options={'HIDDEN'}
     )
 
     def execute(self, context):