GeoJSON (Shape) sources initialized with MGLShape objects should work with predicate filters

[boundsj]

In #7145 we modified MGLGeoJSONSource so that it can be created with an MGLShape. However, since MGLShape does not convey a feature's identifier and attributes properties, we lost the ability to apply a NSPredicate filter to a layer for the source created with a shape.

For instance, this used to work:

    MGLPolygonFeature *feature = [MGLPolygonFeature polygonWithCoordinates:leafCoords count:coordsCount];
    feature.identifier = @"leaf-feature";
    feature.attributes = @{@"color": @"red"};
    
    MGLGeoJSONSource *source = [[MGLGeoJSONSource alloc] initWithIdentifier:@"leaf-source" shape:feature options:nil];
    [self.mapView.style addSource:source];
    
    MGLFillStyleLayer *layer = [[MGLFillStyleLayer alloc] initWithIdentifier:@"leaf-fill-layer" source:source];
    layer.predicate = [NSPredicate predicateWithFormat:@"color = %@", @"red"];
    MGLStyleValue *fillColor = [MGLStyleValue<UIColor *> valueWithRawValue:[UIColor redColor]];
    layer.fillColor = fillColor;
    [self.mapView.style addLayer:layer];

Now, If the layer.predicate is set, the feature is not visible since the attributes cannot be found on the object (shape).

cc @frederoni @1ec5

[boundsj]

This was fixed by #7339