### Godot version

4.0beta12

### System information

all

### Issue description

In `extension_api.json` we have some function that uses parameter typed after a global enum and display it as a bitfield:
```js
{
	"name": "set_button_mask",
	"is_const": false,
	"is_vararg": false,
	"is_static": false,
	"is_virtual": false,
	"hash": 3950145251,
	"arguments": [
		{
			"name": "mask",
			"type": "bitfield::MouseButtonMask" // bitfield prefix here !
		}
	]
},
```

However the global enum's own definition doesn't mention it is a bitfield:
```js
{
	"name": "MouseButtonMask",
	// No "bitfield" field here !
	"values": [
		{
			"name": "MOUSE_BUTTON_MASK_LEFT",
			"value": 1
		},
		{
			"name": "MOUSE_BUTTON_MASK_RIGHT",
			"value": 2
		},
		{
			"name": "MOUSE_BUTTON_MASK_MIDDLE",
			"value": 4
		},
		{
			"name": "MOUSE_BUTTON_MASK_MB_XBUTTON1",
			"value": 128
		},
		{
			"name": "MOUSE_BUTTON_MASK_MB_XBUTTON2",
			"value": 256
		}
	]
},
```

On the other hand, the non-global enums (i.e. the ones defined as part of a class) have this `is_bitfield` field.
So I guess we should add it to global enum too.

### Steps to reproduce

n/a

### Minimal reproduction project

n/a
Dictionary enum_dict;
					enum_dict["name"] = String(enum_name);
					List<StringName> enumeration_names;
					Variant::get_enumerations_for_enum(type, enum_name, &enumeration_names);
					Array values;
					for (const StringName &enumeration : enumeration_names) {
						Dictionary values_dict;
						values_dict["name"] = String(enumeration);
						values_dict["value"] = Variant::get_enum_value(type, enum_name, enumeration);
						values.push_back(values_dict);
					}
					if (values.size()) {
						enum_dict["values"] = values;
					}
					enums.push_back(enum_dict);
				}
				if (enums.size()) {
					d["enums"] = enums;
				}
			}
			{
				
				Array operators;
				for (int j = 0; j < Variant::VARIANT_MAX; j++) {
					for (int k = 0; k < Variant::OP_MAX; k++) {
						Variant::Type rt = Variant::get_operator_return_type(Variant::Operator(k), type, Variant::Type(j));
						if (rt != Variant::NIL) {
							Dictionary d2;
							d2["name"] = Variant::get_operator_name(Variant::Operator(k));
							if (k != Variant::OP_NEGATE && k != Variant::OP_POSITIVE && k != Variant::OP_NOT && k != Variant::OP_BIT_NEGATE) {