Minor fix after 22edbdd

Error was:

TypeError: EnumProperty(..., default='cobie'): not found in enum members
Exception in module register(): \3.6\scripts\addons\blenderbim\__init__.py
Traceback (most recent call last):
  File "\Blender\3.6\scripts\modules\addon_utils.py", line 369, in enable
    mod.register()
  File "\3.6\scripts\addons\blenderbim\__init__.py", line 42, in register
    blenderbim.bim.register()
  File "\3.6\scripts\addons\blenderbim\bim\__init__.py", line 190, in register
    bpy.utils.register_class(cls)
ValueError: bpy_struct "BIMFMProperties" registration error: 'engine' EnumProperty could not register (see previous error)

src/blenderbim/blenderbim/bim/module/fm/prop.py

@@ -41,7 +41,7 @@ class BIMFMProperties(PropertyGroup):
             ("cobie3", "COBie 3", ""),
         ],
         name="Engine",
-        default="cobie",
+        default="cobie24",
     )
     format: EnumProperty(
         items=[