[Feature request]: Option to Adjust Custom Marker Size

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Use case

Currently, when using a custom image as a marker in @googlemaps/react-native-navigation-sdk, the image appears very small and does not provide sufficient visibility or customization.

Expected Behavior:

- A property or method should be introduced to allow developers to specify a custom size for the custom marker image.

- This could be an additional option when adding a marker, such as iconSize or markerSize, which would allow users to scale the image to their preferred size.

It would be helpful if we could adjust the size of custom markers like this:
```
mapViewController.addMarker({
position: { lat: latitude, lng: longitude },
title: 'Your Location',
icon: customImage,
iconSize: { width: 50, height: 50 }, // New property to adjust size
});

```

Or any other better Approach

### Proposal